Psalm 14:1 NRSV says "Fools say in their hearts, 'There is no God.'" The Psalmist is right, that fools often deny the existence of God, but fools are not the only ones who deny the existence of God. In fact, there is no proof for the existence of god at all.  The greatest philosophers and geniuses in history have labored to provide philosophical or scientific proofs for the existence of god, and none of them have endured the test of time. Aristotle's Cosmological Argument, Anselm's Ontological Argument and the Five Ways of Thomas Aquinas have all been dismantled by later philosophers such as Descartes and Kant (who also posited their own unique proofs); the strongest of these is Anselm's, but none of these arguments are indisputable proofs for the existence of God, and even the conciliar statements of Vatican I cannot magically make these arguments true. None of this should be alarming, because salvation is by faith alone, and is not by rational proofs for the existence of God. 

In defense of atheism, it is not the lack of proofs for the existence of god that is a problem, because the real problem is the existence of evil and suffering in the world. How may we believe that God is good or God is love, when there are so many horrors and so much suffering in this cursed world? Wolfhart Pannenberg believes that the existence of these evils in the world is a compelling argument against the existence of god. Pannenberg explains that atheism is justified in its protests due to these evils, because there is no way at this current time to explain how such evils exist in the world, and simultaneously assert that God is good. So Pannenberg agrees with the protests of David Hume, that the suffering and wickedness in the world is incompatible with the postulate that god is a loving and wise Creator. So therefore, atheists are justified in their protests against the existence of God based on this suffering and wickedness, regardless of the famous proofs.  

So long as creation sighs under the dominion of corruptibility and death, creature will also complain and there will be no silencing of the accusations against the Creator by which they show that they are still unreconciled to him. In view of the misery in this world this complaint can even become a contesting of the evidence of God as a loving and omnipotent Creator. Hence only the eschatological consumption of the world will bring definitive proof of God's existence and final clarification of the character of his nature and works. Up to then the world in its autonomy vis-à-vis God and the absurdity of its suffering and wickedness will always provide material enough for the atheism that regards such a world as incompatible with the postulate of a loving and wise Creator. [See D. Hume, Dialogues Concerning Natural Religion (1779) §10-11] [^1]

Pannenberg argues that a fully realized eschatology has failed to prove that God is a good or wise creator, because of the existence of suffering and wickedness in the world. Pannenberg recalls how Voltaire's Candide ridiculed Leibniz's proposal that this is the best of all possible world. Pannenberg goes even further than Voltaire by suggesting that any theodicy (i.e. a solution to the problem of evil) proposed today is ultimately a statement of unbelief; or in words of the Psalmist (c.f. Ps 14:1), only the fool says he has proved the existence of god! 

Pannenberg believes that all atheism is justified at this present time, because only until the last day, at the eschatological consumption of the world, will then anyone be able to see the goodness of God in the world, and be able to know that God is a loving and wise Creator. So Pannenberg believes a 'futuristic theology' is necessary, because any 'realized eschatology' cannot prove the existence of a god, and any such proof is ultimately unbelief. Pannenberg asserts that the existence of God may not be proven before the end of time, when Jesus is fully revealed on the last day. Only then, will the existence of god be indisputably proven. 

In the world's eschatological future, will this process come to an end with the definitive revelation of the glory of God in demonstration of his deity. The eschatological perfecting of the world for participation in the glory of God will also show how wrong is unbelief with its doubting of God's existence. For it will prove the love of Creator for his creatures. In contrast, every rational theodicy has at best only provisional significance. Or may it even be itself already an expression of unbelief? [^2]

Sources:

1. Wolfhart Pannenberg.  Systematic Theology: Volume 3., Eerdmans, 1997, p. 631.
2. Ibid. p. 632.
3. Header Image: Source wikipedia: scan of p46 of The Epistle to the Ephesians 2:12.