Karl Barth is famous (and in some places infamous) for conceiving of God as "wholly other" to human beings. Barth's God is radically transcendent, radically other, and quite hidden. Barth is often criticized on this point for failing to do justice to God's immanence, for making God so inaccessible that speech of God becomes substance-less. How can we make affirmations about God if God is always wholly other and hidden?
Setting aside the fact that this is a rather one-sided picture of Barth's theology, I want to emphasize one of the ways Barth addressed this problem. That is, Barth conceived of God not merely as completely veiled to human beings in general, but particularly veiled in lowly communities. It can be said that, for Barth, there is potential for seeing God in people who suffer and are oppressed, because God makes God's self wholly other to human greatness, and not just to humanity in general.
In order to understand this, we have to understand the origin of Barth's radically transcendent conception of God. The identification of God with the German war effort by many of Barth's contemporaries was the occasion for Barth's decisive NO to liberal theology. Liberal theology, Barth came to see, was a theology of glory; it identified divinity with the glory of humanity, with strength, with success, and we could add, with whiteness. Barth saw this as idolatry.
As black theologian James Cone describes, Barth's criticism of liberal theology was a criticism of "nineteenth century liberalism with its emphasis on the goodness and worth of humanity (which always meant white European humanity)." He adds that, "Every black intellectual is aware that when liberals spoke of 'inevitable progress' and the 'upward movement of Western culture,' it was realized at the expense of blacks who were enslaved and colonized to secure 'progress.'"
Barth was similarly aware that it always meant a divine sanction of human corruption. Nations continually claim God for their side, touting themselves as the innocent and the others as the enemy. "It is sheer blasphemy to relate God to our human strivings in this way," Barth preached. Selfishness, arrogance, hatred, anxiety, and violence are all "completely alien to the innermost being of God," so that if they become the rule of the day, it can only mean "God's innermost being is also completely alien to humankind."
Barth's No to liberal theology, then, was not merely a No to humanity on principle because humanness is evil. His No was fundamentally a No to a human attempt to raise the human up by identifying divinity with human ideas of greatness. Included in Barth's protest against this was an affirmation of God's lowliness. "Against all those who want to be great in this world," Barth said in first commentary on Romans, "I must espouse the standpoint of those little people with whom God makes his beginning." God, he says, "is one-sidedly a God of the lowly."
Because God is a God of the lowly, God can never be identified with human greatness, with human vanity. To identify God with human greatness is to put human glory (which is really arrogance and domination) on a high place, on a pedestal, to be worshiped as an idol.
The hiddenness and otherness of God for Barth is not simply a divine attribute of anti-humanity. We must never forget that God did not come in the form of some kind of extraterrestrial alien being, but as a human. The decisive point is that God came in the form of a lowly human, he came in the form of a servant.
Martin Luther similarly stated that "God destroys the wisdom of the wise" by hiding God's self "in suffering," in "the humility and shame of the cross." It is in this spirit that Barth understands the hiddenness of God in lowly communities. Barth says in his second Romans commentary, the otherness of the other "reminds us of the WHOLLY OTHER."
Consequently, "all Titanism, all mounting of high places, is excluded. ... In order to correspond with their veritable situation men must therefore--bow." That is to say, recognizing that the otherness of the other points to the otherness of God, recognizing that God is the crucified Christ, who veils God's self in a servant-form, who unconditionally identifies God's self with the lowly--all of this means not an exaltation or glorification of human greatness, not a divinization of the human, or a sanctioning of human glory, but, rather, a humbling of one's self, a prostration.
If God is identified with the lowly, then we must makes ourselves lowly to glorify God. If God is identified with the lowly, then we should not look to high places, to human greatness, to domination and success, in order to find God's glory, but should rather look to those who are exploited, oppressed, who suffer at the hands of human glory.
Barth stayed true to this understanding in his Church Dogmatics as well. He says, "God stands at every time unconditionally and passionately on this and only on this side: always against the exalted and for the lowly, always against those who already have rights and for those from whom they are robbed and taken away."
It is in God's revelation in Jesus Christ that we have this knowledge, not in some natural knowledge of God, as the liberal theologians would have it. "Far from being founded upon any sort of general anthropology," Barth says, "our proof is absolutely related to Christology." Precisely in the servant-form lies "a veiling of the divine majesty." This is how "the Word enters hiddenness." Jesus' lowliness is not inconsequential, but is precisely how God reveals God's self as both hidden and revealed. “In [Jesus Christ] God reveals Himself inexorably as the hidden God."
Barth's problem with liberal theology was not merely that they identified God with something human, but that they identified God with human greatness, with human glory, and so exalted themselves even more. They were the exalted ones exalting themselves through theology. They were the ones with rights claiming a divine sanction for furthering their own rights over against the rights of others. Barth declared this to be idolatry.
This critique of idolatry was James Cone's starting point as well. Cone's black theology of liberation was aimed at white idolatry, at the identification of divinity with whiteness, and so at the supposed divine sanction of white supremacy. Cone's protest against this idolatry was to boldly proclaim that God is not a God of whiteness, but is wholly other to the white God, and so identifies with oppressed blacks and fights for them.
Similarly, Barth's theology can be described as a black theology. It at least lends itself to black theology. This is so because, for Barth, God reveals God's self in the servant-form of Jesus Christ. The human constructs idols of human glory that are at odds with lowly servant-forms, and so God elects the servant-form to veil and unveil God's self. Jesus is black because Jesus reveals God's self in human lowliness and suffering.
To fail to understand this about Barth's theology is to make Barth's God an abstract concept of otherness, reducible to the idea of the "unconditioned" or the "undeconstructable" in philosophy. Barth again and again insists that the hiddenness of God is not this, that God's hiddenness is not merely a general mysteriousness, or a general concept of that which is beyond human conception. God veils God's self, and God does this not just in defying human thinking, but in veiling God's self in what humans deem undesirable, unworthy, and unwelcome.
To fail to witness to God's hiddenness in those who are lowly is to fail to witness to the Word of God. To fail to see Christ in the otherness of those who are suffering is to fail to see Christ altogether. To fail to see God suffering with the black community is to fail to see the cross.
And even further, to fail to understand one's self as responsible for acting on behalf of the poor and oppressed is to fail to understand our God-given responsibility. As Barth says, we cannot hear and believe God's identification with the lowly "without feeling a sense of responsibility in the direction indicated." Specifically, he says,
There follows from this character of faith a political attitude, decisively determined by the fact that man is made responsible to all those who are poor and wretched in his eyes, that he is summoned on his part to espouse the cause of those who suffer wrong. ... He cannot avoid the question of human rights. He can only will and affirm a state which is based on justice. By any other political attitude he rejects the divine justification.According to Barth, God is particularly concerned for the poor and oppressed, particularly concerned for their liberation. To hear and believe God's Word then behooves one to be responsible for the poor and oppressed, and to work for their liberation.
So then, to hear and believe God's Word today means to be moved by the suffering of the black community, and to act accordingly. To fail to do so is, as Barth said, to reject divine justification.
 James H. Cone, A Black Theology of Liberation, 40th anniversary ed. (Maryknoll: Orbis Books, 2010), 19-20)
 Cone, 20.
 Karl Barth, A Unique Time of God: Karl Barth's WWI Sermons, ed. and trans. William Klempa (Louisville: Westminster John Knox Press, 2016), 109.
 Barth, A Unique Time of God, 111.
 Karl Barth, Der Römerbrief, 1st ed., quoted in George Hunsinger, "Toward a Radical Barth," in Karl Barth and Radical Politics (Philadelphia: The Westminster Press, 1976), 225.
 Martin Luther, Heidelberg Disputation, in The Annotated Luther, Vol. 1: The Roots of Reform, ed. Timothy J. Wengert (Minneapolis: Fortress Press, 2015), 99.
 Karl Barth, The Epistle to the Romans, 6th ed., trans. Edwyn C. Hoskyns (New York: Oxford University Press, 1933), 444.
 Barth, The Epistle to the Romans, 444.
 Karl Barth, Church Dogmatics, Vol. II: The Doctrine of God, Part 1, eds. G. W. Bromily and T. F. Torrance, trans. T. H. L. Parker, W. B. Johnston, Harold Knight, and J. L. M. Haire (New York: T&T Clark, 1957 [repr. Peabody: Hendrickson Publishers, 2010]), 386.
 Karl Barth, Church Dogmatics, Vol. I: The Doctrine of the Word of God, Part 2, eds. G. W. Bromily and T. F. Torrance, trans G. T. Thomson and Harold Knight (New York: T&T Clark, 1956 [repr. Peabody: Hendrickson Publishers, 2010]), 44.
 Barth, CD I.2, 37.
 Barth, The Epistle to the Romans, 369.
 Barth, CD II.1, 386-387.