Karl Barth

Karl Barth is the named theologian for the exclusivism section of the DCT A2 paper. However, one of the things we will consider here is whether he actually is an exclusivist or whether he leans more towards universalism.

You need to know what Barth taught about religion, the Wordnatural knowledge and revelation, and predestination and election.  You may already have some understanding of Barth's theology from the AS Knowledge of God topic.

There is an excellent 30 minute online programme about Barth part 1 here and part 2 here.

Is Barth's theology exclusivist? 

One of the things that you need to consider is whether you think that Barth's theology was exclusivist or not. 

  • On the one hand his rejection of natural theology and his emphasis that any knowledge of God must come from God's special revelation in Jesus imply exclusivism.
  • However, his insistance that God is free to do whatever he chooses and can reveal himself through anything even a dead dog suggest that God could be revealed through non-Christian religions too.
  • Barth's reinterpretation of the doctrine of predestination and election can be interpreted to imply universalism.

Ultimately, you need to look carefully at Barth's ideas and consider for yourself what camp you would put him in.

Biography and overview:


Prof David Clough describes Barth's theological journey here.

Karl Barth was born in 1886 in Basel (Switzerland). His father was a paster and Barth was brought up within the Protestant Christian tradition.  He studied theology at university, first at Bern, then at Berlin, Tubingen and Marburg.  

We could use an analogy to explain Barth's rejection of liberal theology.  Liberal theology trusts human beings and treats them like moral adults who are fit to make up their own mind about how to behave.  Barth felt that by supporting WWI people had shown that they were not yet fit to be trusted with important moral decisions and they still required a moral parent (God) to tell them how to behave.

During his theological training he was taught by many eminent liberal Christian theologians.

However, be became disenchanted by liberalism during WWI. Liberal theology trusted human reason to derive moral codes and encouraged Christians to think critically about which parts of the Bible to follow.  Barth was particularly shocked that many of the leading liberal theologians who had taught him supported the Kaiser's war policy.  He felt that if liberal values could lead to an endorsement of war then liberal Christianity was misguided and a return to traditional values and ways of doing theology was essential.


‘The neo-orthodox movement was characterized by the attempt of theologians to rediscover the significance for the modern world of certain of the doctrines that had been central to the older Christian Orthodoxy. 

Consequently, the proponents stood in a complex relationship to the liberalism that preceded the newer thinking. 

On the one hand, neo-orthodox theologians followed the older liberalism in viewing the Enlightenment as a given, and as a result with their liberal forebears they accepted biblical criticism. 

On the other hand, the younger thinkers rejected what they saw as the cultural Christianity of liberalism, which arose out of the emphasis on natural theology.  They were gravely concerned that the Protestant liberalism had been so intent on making the Christian faith palatable to the modern mindset that it had lost the gospel.’

Twentieth Century Theology, 1993, by S.J. Grenz and R. E. Olson

Barth is described as a Neo-Orthodox theologian. Neo-Orthodoxy emerged as a reaction to liberal theology and looks back to tradition for guidance. Protestant theologians like Barth were influenced by the ideas of the sixteenth century Reformers like Calvin.  Neo-Orthodox theologians shared some of the Reformers' central theological interests including a focus on human sinfulness and the centrality of the Bible.

Barth's first important work was a commentary on Paul's letter to the Romans published in 1919.  It was very different to the types of commentary that people were used to.  Instead of deep textual analysis and historical criticism Barth's Epistle to the Romans focused on his own experience of reading Paul's letter.  He stressed God's divinity and argued that God was radically other when contrasted to human beings.  This concept of the 'otherness' or strangeness of God is central to his theology as his steadfast conviction that God's divinity gives him complete freedom to act however he liked.  

Barth then wrote a commentary on St Anselm which he called Faith Seeking Understanding The title was a quotation from something Anselm had once wrote to describe his own work and Barth took this as the starting point of theology. 

In Bath's view, all theology had to be done from the perspective of faith. Barth rejected the idea that reason could be used to evaluate or criticise faith (as was done by post-Enlightenment thinkers) because this would be using falible human reason to critique God's truth.  Equally, Barth rejected the idea that reason could be used to support faith (as happened in the Natural Theology of people like Aquinas and Paley).

‘Any attempt to ground the truth of God’s Word in human reasoning, however devout and sincere, inevitably leads to theology being subverted by human, historical modes of thought and thus to “anthropocentric theology,” the evil against which Barth fought so hard.’

Twentieth Century Theology, 1993, by S.J. Grenz and R. E. Olson

In 1921 Barth became a theology professor at Gottingen University before moving on to Munster University in 1925.  From here he began his next important work which he originally titled Christian Dogmatics. It was first published in 1927 but Barth entirely reworked it and the first volume of the renamed Church Dogmatics was republished in 1932 after he had moved again to the University of Bonn.  Church Dogmatics was a work of systematic theology based on his lecture notes and eventually ran to twelve volumes!

In 1934 the Barmen Declaration (largely written by Barth) was published.  It emerged out of a meeting of representatives from the German Evangelic Churches. The document contains many ideas which appear to reflect exclusivism but (as we shall explore later) the document was as much about rejecting Nazism as about asserting Christian superiority over non-Christian religions.

The famous Barth/Brunner debate about Natural Theology emerged in the same year as the Barmen declaration.  Emil Brunner wrote an essay critiquing Barth's views and defending the value of Natural Theology.  Barth responded with an essay of his own entitled Nein! (No) and rejected Brunner's points.

Barth refused to take the oath of allegiance to Hitler and was fired from his University Chair.  He left Germany and went back to Switzerland and to Basel University where he continued to work, teaching and writing.  He died in 1968. He legacy is hugely important.  In their book Twentieth Century Theology (published 1993) Stanley Grenz and Roger Olson state

‘When future historians of theology look back on the twentieth century there is little doubt who they will  name as its single most influential Christian thinker: Karl Barth.’

Key ideas:

Natural theology:

As you may remember from the knowledge of God module, Barth rejected any possiblity of natural knowledge of God. 

He argued that God is so radically other that he is inaccessible to human reason and the fallen nature of creation means that God's image is entirely hidden from us. Consequently no knowledge of God is possible except through Special Revelation.

Barth's rejection of Natural Theology drew on the ideas of Immanuel Kant and Soren Kierkegaard.

Look at the notes on Hick to see how he uses the same Kantian distinction in a different way.

  • Immanuel Kant's distinction between noumena and phenomena is useful background for Barth's views.  'Phenomena' refers to the world as we experience it. We base our knowledge on our experience.  However, we have no one of assessing whether our experience is reliable.  The noumena (the way thing really are in themselves) is inaccessible to us. Therefore, according to Barth, knowledge of God as he is in himself is impossible to access through reason.  We can only talk about what we experience, not what God really is.  Basing knowledge of God on human experience will lead to use projecting hopes and desires onto God (in the way that Feuerbach imagined). Thus God cannot be known through reason.

‘For Kierkegaard, because of human sinfulness and the whole otherness of God, God’s truth and human thought can never be smoothed out into a rational synthesis.  Instead, the paradoxical truths of God’s self-revelation must be embraced in a leap of faith by the finite human mind.’

Twentieth Century Theology, 1993, by S.J. Grenz and R. E. Olson

  • Soren Kierkegaard rejected the supremacy of reason.  Kierkegaard compared Christianity with the religion of Socrates.  Socratic religion assumes that the individual in some sense knows truth and all that needs to happen is for it to be brought out.  Reason has a role in drawing out that truth.  However, this is different to Christianity which assumes that the individual is ignorant and needs a teacher (i.e. Jesus).  The paradoxes in Christianity (for example the idea that God can become man or that a transcendent God can intervene in human affairs) mean that Christianity can only be accepted by faith.  The paradoxes offend reason and mean that religious belief can never be rational.

In the Barmen Declaration this rejection of Natural Theology is made apparent and Barth asserted that knowledge of God is impossible outside the special revelation of God in Jesus.

  • Emil Brunner disagreed and in 1934 wrote an essay that argued that Natural Knowledge - though limited - was a useful 'point of contact' which prepares the mind of the non-Christian and makes it ready to receive the gospel.  Brunner argued that the fall had damaged the image of God in mankind but had not totally destroyed it.  Brunner used examples from the Old Testament to support the belief that creation revealed God and he argued that his position was closer to Calvin's beliefs than Barth's was.  

The Word:

Barth describes the Word of God as three-fold.

  1. Living Word (Jesus)
  2. Written Word (Bible)
  3. Preached Word (Church)

Jesus is the living Word of God because he is God's self-revelation through which God communicates with human beings and reveals himself to them.  Jesus is God's 'YES' to humanity which enables people to know him.

Barth says 

'Jesus Christ our Lord...In this name two worlds meet and go apart, two planes intersect, the one known and the other unknown. 

The known plane is God's creation, fallen out of its union with him, and therefore the world of the "flesh" needing redemption.  

This known plane is intersected by another plane that is unknown - the world of the Father.'

Barth goes on to explain that the historical Jesus, the point when God became observable in history is the point where the unknown God meets the known world. The point at which God intervenes in the world and sends Jesus.

When Barth describes Jesus as the 'Word' of God he is alluding to John's Gospel which describes Jesus as 'The Word made flesh'  i.e. God's spirit incarnate.

'Word' should not be taken in the narrow sense to mean a literal word.  God's Word is his message but it is more than spoken words said.  God's Word is an event which happens to humans when they encounter him.

As God's Word should be properly understood as an event it follows that the human words of the Bible and Church preaching cannot be literally God's Word.  They are limited and can only convey the experience of God to a degree.  We could explain this further by use of two analogies;

Note: It is important to understant that this effect is not brought about by human effort.  The Bible is not a catalyst because it is well written or preaching a catalyst because the priest speaks well.  Barth is categorical that nothing humans can do can invoke God.  They act as a catalyst only because God in his infinite wisdom and divine love chooses to use them and meet humans at the point where they hope to find him.  It is through Grace that the Church contains the Word of God, not through any special achievements of humans. 

  • The Bible is a witness to the Word of God. The Bible is a record of Jesus. The Old Testament points toward him through prophecies and the New Testamnet contains biographies of his life and accounts of the Church that he created. Preaching similarly witnesses to the Word of God in the life of the Church.  Barth said ‘What we have in the Bible are ...human attempts to repeat and reproduce this Word of God in human words and thoughts and in specific human situations.’ 
  • Both the Bible and Church preaching can act as a catalyst and help people to experience the event of God's Word in their lives.  Barth describes the Bible as 'pregnant with revelation' i.e. it brings forth revelation but is not itself identical to that revelation.

‘For Barth, the Bible is the Word of God because again and again…God uses it to produce the miracle of faith in Jesus Christ.’

Twentieth Century Theology, 1993, by S.J. Grenz and R. E. Olson

They are God's word in an instrumental sense rather than in an instrinsic sence (lead to it rather than are it).  Barth himself had experienced the way in which reading the Bible could result in the reader experiencing God's Word for themselves.  When he had read Paul's letter to the Romans he felt as though Paul were speaking to him across the centuries.  

Barth's beliefs about the three fold word of God enable him to maintain the central importance of the Bible without provoking the problems that emerge from a fundamentalist stance.  He did not entirely reject the historical critical methods of liberal scholarship but he thought that they were not essential - the reader could experience God's Word without knowing who wrote what, when and why.


All religions, including Christianity, are a human construct because 'religion' is something that human beings create to try to find God.  Therefore, religion is fallible and limited.  It is not true.

Barth says that the nature of Christianity is no different to the nature of non-Christian religions.  All religions have the same essence because they are all about trying to reach sanctification (holiness) and justification (righteousness). In religion, people create ceremonies, rituals, creeds and moral rules and punishments to try to help them find God, understand God and please God.  

Barth argues that Christianity is superior to non-Christian religions but only because God chooses to reveal himself through it.  I.e. it is superior because of what God does through it, not because of what Christians themselves are trying to do.

'Revelation singles out the Church as the locus of true religion.  But this does not mean that the Chrsitian relgion as such is the fulfilled nature of human religion.  It does not mean that the Christian religion is the true religion, fundamentally superior to all other religions.  We can never stress too much the connection between the truth of the Christian religion and the grace of revelation.'

Barth uses the following analogy to explain his point:

  • A human being cannot be truly good by their own efforts (because they are fallen and inclined towards sin).  If then they are good it is because they are made good through the grace of God.
  • Likewise, God cannot be truly known and nor can he be accessed by human means (because he is radically other).  If then a religion is true it can only be true because God has made it true through his own gracious action.

Predestination and Election:

The sixteenth century protestant reformer John Calvin taught the doctrine of double predestination.  His argument went as follows:

  • All humans are sinful.  No one deserved heaven.
  • Salvation is an undeserved (unmerited) gift which is freely given by God.
  • A free gift cannot be related to any conditions, nor can it be earned (for then it would not be a gift).
  • For salvation to be truly a free gift it must be given to people totally independent to their actions.
  • Thus God must decide before a person is born whether they are 'elect' and going to heaven or 'reprobate' and going to hell. 

Note:  Calvin did believe that good people go to heaven and bad people go to hell but he believed that they are good or bad BECAUSE they are elect or reprobate.  Thus the type of life they lead comes from the elected/reprobate status rather than the other way around.

  • The elect receive God's grace and this has a positive impact upon the way that they live their life.  The reprobate do not have God's grace and act in the way that you would expect sinful humans to act.

Barth regarded the doctrine of predestination as a 'scandal' and yet his own insistence on God's freedom potentially could have lead him down the same lines as Calvin.

Instead, Barth radically reworked the doctrine of predestination.  He said that God himself is the one elected to be the reprobate.  He takes the punishment so that humans can have the reward.

Barth wrote:

'For if God Himself became man, this man, what else can this mean but that He declared himself guilty of the contradiction against Himself...that He made Himself the object of the wrath and judgement to which man had brought himself; that He took upon Himself the rejection which man had deserved; that he tasted Himself the damnation, death and hell which ought to have been the portion of fallen man?'

Barth, Church Dogmatics

This type of theology is sometimes termed 'substitution' theology because God substitutes himself for sinners.

What he meant is that by becoming human God takes on the characteristics of the human condition (i.e. sinfulness).  Thus although Jesus did not himself sin he plays the part of the sinner and takes the punishment that the sinner deserves.

Barth went on to write:

'When we say that God elected as His own portion the negative side of the divine predestination, the reckoning with man's weakness and sin and inevitable punishment, we say implicitly that this portion is not man's portion.'

He continued:

'Rejection cannot again become part of the portion or affair of man. The exchange which took place at Golgotha, when God chose as his throne the malefactor's cross, when the Son of God bore what the son of man ought to bave borne, took place once and for all in fulfilment of God's eternal will and can never be reversed. There is no condemnation - literally none - for those that are in Christ Jesus. 

However, do look at the last sentence of the quotation above. Are only Christians those 'in Christ Jesus' or did Barth mean that all people are in Christ Jesus because Jesus' death was for all?

The implication seems to be that through Jesus' death all people become the Elect.  This would mean that all people would go to heaven.  Many scholars of Barth believe that he was a universalist (someone who believes that all people go to heaven).  Gretz and Olsen deal with this question in their chapter on Barth

'Does this amount to the doctrine of apokatastasis or universalism?  In his written responses to this question Barth refused to give a straight answer: “I do not teach it, but I also do not not teach it”! Nevertheless, we can guess what the answer must be.  As Catholic scholar Hans von Balthasar pointed out, “it is clear form Barth’s presentation of the doctrine of election that universal salvation is not only possible but inevitable.  The only definitive reality is grace, and any condemnatory judgement has to be merely provisional.”’

Twentieth Century Theology, 1993, by S.J. Grenz and R. E. Olson

It is worth nothing that Barth's refusal to give a straight answer may well have been dictated by his own doctrine of God.  Barth's central thesis is that God is free to act however he likes.  This would mean that Barth would not have felt able to make categorical statements about what God would or would not do with regard to the salvation of non-Christians.

Barmen Declaration:

You can read the Barmen Declaration here.

'...we confess the following evangelical truths:

1. "I am the Way and the Truth and the Life; no one comes to the Father except through me." John 14:6

...Jesus Christ, as he is attested to us in Holy Scripture, is the one Word of God whom we have to hear, and whom we have to trust and obey...

...We reject the false doctrine that the Chruch could and should recognize as a source of its proclamation , beyond and beside this one Word of God, yet other events, powers, historic figures and truths as God's revelation."

Barman Declaration.  

The Barmen Declaration was written in 1934 in opposition to Christians in Germany who had shown support for the Nazis.  The Declaration comprises of six statements all of which begin with a quotation from the Bible.

Below is a paraphrasing of the key points of the Barmen Declaration.

  1. Jesus is the one Word of God.  There are no other sources of revelation. (See box to the right).
  2. Christians are expected to devote all areas of there life to Jesus.  There are no areas which are not claimed by him.
  3. Jesus acts in the Church through 'Word and Sacrament'.  The Church belongs to Jesus.  It should not act in the service of anyone else.
  4. Within the Church no one should have authority over others (the role of ordained ministers is to serve).  
  5. God allows the State to keep the peace and maintain order and justice. However, the State should not take over the role of the Church and it should not claim to be the only thing to order human life.
  6. The role of the Church is to act for Jesus and 'deliver all people, through preaching and sacrament, the message of the free grace of God.'

The Barmen Declaration is sometimes taken as evidence that Barth's theology is exclusivist.  The first truth (quoted in the box above and to the left) is particularly exclusivist in tone.  The traditional Christian beliefs about Jesus are reasserted, revelation outside Jesus is denied.  Truth number three reaffirms the traditional view of the Church as the body of Christ on earth and could be related back to the extra ecclesium nulla salus principle.

However, points 4 and 5 and, to perhaps a lesser extent, 3 all seem to relate much more explicitly to the political situation than the the relationship between Christianity and non-Christian religions.  Barth rejects the idea that the Church can be used in the service of anything other than God.  He rejects the idea that the State should claim absolute authority in life or that certain figures should be given and authoritative role within the Church.

That said, even if these statements are directed primarily at the State rather than non-Christian religions they do seem to have parallels with arguments made by exclusivists about truth and authority.  For example, these statements reflects Hendrick Kraemer's fears that contemporary society's rejection God-given moral absolutes leaves a power vacuum and 'pseudo absolutes' rise up to take their place.  In other words, loss of absolute moral values from religion has enabled governments and regimes to impose their views on people.  Lesslie Newbigin deals with the same issue when he says that Christians should be prepared to make a stand when the values of society conflict with the values of Christianity. He expects ideological conflict as he says that there is a

'radical contradiction between the gospel message and the wisdom of the world'

Lesslie Newbiggin, The Gospel in an Pluralist Society

He called for Christians to live their lives as a 'hermeneutic of the gospel' (i.e. put Jesus' teachings into practice).  Newbigin says that Christianity has the right and the duty to do this because of where it comes from.  He says

'Christianity began with the proclamation of something authoritatively given'

He explains that Paul did not create his message but 'passed on' something that he felt he had received from God.  Kraemer makes a very similar point and says

'The only valid and indestructible law can be the Law from above and not from within.'

[Christianity] claims as its source and basis a divine revelation'.

Hendrick Kraemer, The Christian Message in a Non-Christian World.

This has parallels with phrases found in the Barmen Declaration;

'The inviolable foundation of the German Evangelical Church is the gospel of Christ Jesus as it is attested to us in Scripture.'

Barmen Declaration

The claims of the Church are built on the 'foundation' of Jesus' message as found in the gospel.  The basis of their authority ultimately comes down to faith.  This again relates back to a point made by Kraemer who says that

'To demand a rational argument for faith is to make reason, that is, man, the standard reference for faith.'

Kraemer and Barth both think that human reason is fallible and is consequently an insufficient foundation for knowledge of God or knowledge of morality.


Barth's theology is born out of a dissatisfaction with liberal theology so you might want to begin by considering whether Barth's criticisms of liberal theology were justified.

  • Is he right to reject natural theology and to reject the idea that we can use reason to gain knowledge of God?
  • Is he correct in his belief that liberal theological methods are likely to lead to people projecting their desires onto God and then using reason to justify them?

Misinterprets Scripture:

Responses to Barth's interpretation of Scripture were mixed.  His commentary on Romans divided opinion.

‘Some liberal biblical scholars and theologians dismissed it as the rantings of a religious enthusiast, while others hailed it as a recovery of the true spirit of the Reformation.  Some of Barth’s own teachers, including Harnack and Herrmann, were puzzled by its unhistorical and uncritical approach to the Bible…however, numerous pastors, teachers and theologians found it a badly needed corrective for Christian theology moving into the twentieth century.’

More generally, his interpretation of what Scripture is was challenged by both liberal's and conservatives.  Liberals thought that he placed too much trust in it whilst conservatives/fundamentalists objected to the fact that he did not believe it was the literal Word of God.

‘Barth’s view of Scripture caused much controversy and criticism.  Liberals accused him of elevating the Bible to a special position that nearly equaled the traditional doctrine of verbal inspiration, thus removing it form historical critical inquiry,  Conservatives, on the other hand, assailed Barth’s subordination of Scripture to a nonpropositional even of revation and his explicit denial of its inerrancy, some going so far as to label his theology a “new modernism”.’

Furthermore, Barth seems to be inconsistent with regard to Scripture.  He rejects the idea that it is the inerrant Word of God and yet in his own writing he refers to it to justify his theological arguments as though it is the final arbiter of truth.


Barth's rejection of the role of reason meant that he has been accused of fideism. There are several reasons why we might want to challenge Barth's utter rejection of the role of reason.  These objections are theological, methodological and practical.

Theological problems are as follows:

  • There are theological reasons to believe that reason can lead humans to a knowledge of God.  Humans are created in God's image, human rationality is a part of that.  People like Brunner would argue that this provides us with a 'point of contact' between God and man and a starting point for theology. Brunner believed that Calvin did think that some Natural knowledge of God was possible.
  • Natural Theology (which relies on reason) appears to have been a fruitful method of theology in the past.  People like William Paley and Thomas Aquinas made extensive use of it.
  • The Bible seems to support the idea that some natural knowledge of God is possible and this may well be taken to imply that reason can lead to knoweldge of God.

Methodological problems:

  • If reason is rejected then theology becomes isolated.  There is no possibility of dialogue between theology and other disciplines.

Practical problems:

  • Reason is a fundamental part of human nature.  To expect people to have faith without offering any rational understanding of this is impossible and would lead to the death of religion. 

However, one could also argue that Barth has returned to what theology should be about.  

  • To allow 'reason' to evaluate faith is - arguably - perverse because it involves humans challenging God (i.e. the stupid to challenge the wise!).  (See Kraemar quotation above).
  • Placing reason above all else also demotes religion and theology which become answerable to disciplines like science. 
  • Rational theology has led to deism and 'God of gaps' type arguments in which belief seems to be undermined.  
  • The Bible supports the idea that religious truth may conflict with reason and celebrates the virtue of faith.  Paul's first letter to the Corinthians makes clear the fact that Christianity may seem like foolishness to the philosopher:  'Where is the wise person? Where is the teacher of the law? Where is the philosopher of this age? Has not God made foolish the wisdom of the world? For since in the wisdom of God the world through its wisdom did not know him, God was pleased through the foolishness of what was preached to save those who believe.  Jews demand signs and Greeks look for wisdom, but we preach Christ crucified: a stumbling block to Jews and foolishness to Gentiles, but to those whom God has called, both Jews and Greeks, Christ the power of God and the wisdom of God. For the foolishness of God is wiser than human wisdom, and the weakness of God is stronger than human strength.' (1 Corinthians 1:20-25).  When Jesus appeared to doubting Thomas after his resurrection he says 'blessed are those who have not seen and yet believe'. (John 20:29)
  • Furthermore, we may agree with Barth that liberal rational theology can become self-serving as it is all too easy to devise 'rational' arguments to justify our own desires, prejudices and weaknesses.


Finally, one could accuse Barth of Christomonism. Gavin D'Costa argued that exclusivist doctrines with stress that God can only be known through Jesus are wrong because they oppose the idea of the Trinity.

The whole point of the Trinity is that God is three in one. Three persons, one God. Each person (Father, Son and Holy Spirit) are fully God - i.e. all are authentically God - but they are not the whole of God. To say that God can only be known through Jesus ignores the role of the Father in creating the world and ignores the role of the Holy Spirit which acts in the world.

So, back to the question - was Barth an exclusivist?

Ultimately this is something you need to decide for yourself on the basis of your knowledge of Barth's ideas.

Certainly he bears some similarity with exclusivists. His emphasis on the the singular importance of Jesus and the utter dependence on Christ for Salvation are beliefs that exclusivists would share. However, so too would inclusivists like Rahner (though they might tend to express the idea in slightly more moderate terms). Belief that salvation comes from Jesus and belief that Jesus was God incarnate are held by both inclusivists and exclusivists. Barth's rejection of Natural Theology strikes a blow for inclusivists or pluralists who argue that non-Christian religions have a way of knowing God without using the Bible or knowing Jesus which might point back towards exclusivism as God can only be known through God's revelation and God's revelation is found in Jesus.The Barmen Declaration's emphatic focus on Jesus as the sole source of authority certainly sounds exclusivist in tone.

However, Barth's belief in God's freedom which means that God could reveal himself through anything if he chose implies that it must at least be possible for God to reveal himself through non-Christian religions. Likewise, if Von Balthasar was right and Barth's doctrine of election results in universalism, it is hard to label him an exclusivist since many exclusivists maintain that non-Christians will end up in the fires of hell.

Further Reading:

Text of the Barmen Declaration here.

Two minute video clip of Barth talking about the impact of the Barmen Declaration (subtitled) here.

Video clip of Barth describing his theology of revelation (subtitled) here.

David Clough (university of Chester) traces Barth's theological development (video) part 1 is here and part 2 is here.  Parts of it are quite technical but it deals with a lot of the key issues that the syllabus covers and it is really useful material to stretch and challenge you!

Less relevant, but still useful.  This video is about the impact and influence of Barth's ideas found here.

Lots of links on Barth here.