During my undergraduate research into the wide and wondrous theological landscape of Karl Barth’s rejection of natural theology, I came across some criticisms of Barth made by Martin Luther King Jnr.
King made these criticisms in 1952, centring them around two main points. First, the [liberal] theologian must part with Barth in his rejection of natural theology. This is because:
‘we find God in the beauty of the world, in the unpremeditated goodness of humanity, and in the moral order of reality. Second, Barth emphasises the unknowableness of God, but if God is unknowable one wonders how Barth came to know so much of the ‘’Unknown God’’ .
Here King shows his lean towards the theology of ‘19th century liberal protestants, who viewed human culture as being endowed with revelatory potential’ .
In the end, though, King somewhat affirms Barth’s theology,
‘In spite of our severe criticisms of Barth, however, we do not in the least want to minimize the importance of his message. His cry does call attention to the desperateness of the human situation. He does insist that religion begins with God and that man cannot have faith apart from him. He does proclaim that apart from God our human efforts turn to ashes and our sunrises into darkest night. He does suggest that man is not sufficient unto himself for life, but is dependent upon the proclamation of God’s living Word, through which by means of Bible, preacher, and revealed Word, God himself comes to the consciences of men. Much of this is good, and may it not be that it will serve as a necessary corrective for a liberalism that at times becomes all to shallow?’ 
King’s rejection of Barth’s “no” to natural theology seems short-sighted.
‘Christianity is the protest against all the high places which human beings build for themselves’ (Barth C.D IV/II p.524).
When viewed through the lens of World War One and German preoccupation with Social Darwinism, World War Two and the Barmen Declaration, his rejection of natural theology is more understandable. Barth’s stance pushed against the claims of national socialist ideology by aiming at its roots .
What Barth rejects is natural theologies,
‘autonomous rational structure’ (Torrance), , and its ‘self-determining knowledge of God which is absent of Jesus the Christ. The importance of the revelation of Jesus Christ is that He teaches us that we are‘ human beings and not pets’ (Olasky) .
Natural theology, it could be argued, bolstered the clinical one-sidedness of Scientism; Nazi dehumanization programs, rationalised ignorance, the humanist deification of humanity (seen in the führerprinzip), the Nazi gas chambers, “re-education” camps, total war, eugenics, racism and slave labour.
Barth’s ”no” to natural theology is seen better under the light of his sociopolitical context. It’s a much larger critique than that of 19th Century theology. Barth’s words fall as a warning to those who sought to detach Christian theology from Christ. It’s a criticism of those who attempted to synchronise Christian theology with the tentative conclusions of the disciples of Frederic Nietzsche, Karl Marx, Sigmund Freud and Charles Darwin. All of whom can be found to have had a direct and indirect influence on German thought, specifically, National Socialism.
This opposition was worked out in the Barmen declaration; authored by Barth as part of the Confessing Churches stand against National Socialism in the 1930’s.
‘We reject the false doctrine, as though there were areas of our life in which we would not belong to Jesus Christ, but to other lords–areas in which we would not need justification and sanctification through him’ (Barth, 8.15 second thesis, Barmen Declaration 1934).
In 1962, ten years after his initial criticisms, King met Barth. Despite their differing position on natural theology they shared some visible common ground in their eventual opposition to the Vietnam War. Barth ‘called for opposition to the conflict in Vietnam, stating, “It is not enough only to say, ‘Jesus is risen,’ but then remain silent about the Vietnam War’ . It’s possible to hear echoes of Barth in King’s words to Riverside Church in New York on the 4th April, 1967.
“There comes a ‘a time to break the silence’ because ‘’a time comes when silence is betrayal.”
This “point of contact” with Barthian theology is displayed in the overall content of King’s speeches. It’s one that can be measured alongside the Barmen declaration and matched with Barth’s own opposition, not only to the conflict in Vietnam, but also to Nazism.
Barth and King stand as examples. Both challenged ideologies with theology. Challenging old and new, political and cultural ideologies that had moved, or were moving from being a servant towards being a master. Each show that the world benefits when Christian theology stands and then seeks to steer humanity away from the rocky shores of its own making, such as the seductive Siren calls of Machiavellian agendas and unruly ‘isms.’
As the Lutheran, Gene Veith, wrote,
‘Nazism was a calculated crusade to deny the transcendence of God and usurp Christianity’. Theology must challenge ‘the ideas that led to Auschwitz with special scrutiny. This is especially true when those ideas, often adopted uncritically, are still in vogue today’ .
Today, its relevance calls Christians – theologians – regardless of skin colour or country, to stand side by side in a push back against the stream. To push back against the mudslide of agendas carried along by propaganda machines which often feed off of division, drama and a one-sided, segregated, party-line.
No where is this more evident in theology today, than in the virulent misuse of liberation theology. What arose with great promise as it looked towards reconciliation, now only appears to be a selective slingshot in the verbal arsenal of “progressive” stone-throwers. Causing a breakdown of dialogue which has all but confirmed the suspicions of their conservative brothers and sisters.
It’s here that we might find Barth and King’s voices of resistance. In this what might be heard is a collective “no”; the call for the reformation and therefore liberation of liberation theology.
King, 4th April, 1967 (transcript):
 King Jnr, M.L. 1952 Karl Barth’s conception of God sourced 17th August 2012 from http://mlk-kpp01.stanford.edu/primarydocuments/Vol2/520102BarthsConceptionOfGod.pdf (pp.105-106)
 McGrath, A.E. 2001 a scientific theology: nature vol1. T&T Clark Ltd. Edinburgh, Scotland (p.255)
King Jnr, M.L. 1952 Karl Barth’s conception of God sourced 17th August 2012 from http://mlk-kpp01.stanford.edu/primarydocuments/Vol2/520102BarthsConceptionOfGod.pdf (p.106)
 Gorringe, T.J 1999 Karl Barth: Against Hegemony Christian theology in context Oxford University Press New York (p.3)
 Torrance, T.F. 1994 Preaching Christ today: the Gospel and scientific thinking Wm. B. Eerdmans publishing Co. Grand Rapids, MI, USA (p.70)
 Olasky, M 2003 Standing for Christ in a Modern Babylon Crossway Books, Good News publishers Wheaton, IL (p.80)
 Chung, S. W. 2006 Karl Barth and evangelical theology: Convergences and divergences Milton Keynes, Paternoster Press. UK (p.199) citing George Hunsinger
 Veith Jnr, G.E. 1993 modern fascism: the threat to the Judeo-Christian worldview Kindle for P.C. Ed.
1. The Princeton University Chapel, Dr. King on the Chapel steps, with Karl Barth (pictured on the left), April 29, 1962.
2. A stroll on campus at Princeton University,
*”The Calling to Speak is Often a Vocation of Agony” (King, ‘Beyond Vietnam‘)