The problem of evil is the oldest and most persistent challenge to theism - the question of how a God who is omnipotent (all-powerful), omniscient (all-knowing), and omnibenevolent (perfectly good) can permit the suffering and moral evil that characterize human experience. It is voiced in the Bible itself with extraordinary force: Job's protest against innocent suffering, the Psalms of lament, Jeremiah's confessions, and Habakkuk's complaint constitute a biblical tradition of theodicy that precedes all philosophical formulation. In the Western philosophical tradition, the problem has generated the most sustained literature in philosophy of religion, from Leibniz's Theodicy (1710) through Hume's Dialogues Concerning Natural Religion (1779), J.L. Mackie's 'Evil and Omnipotence' (1955), and Alvin Plantinga's Free Will Defense (1974) to Marilyn McCord Adams's work on horrendous evils. The debate represents philosophy's most sustained engagement with the biblical texts on suffering.
Biblical Texts Engaged
Job 1:21 - 'The Lord gave, and the Lord has taken away; blessed be the name of the Lord' - is Job's initial response to catastrophic loss. The book of Job is the Bible's primary philosophical treatment of the problem of innocent suffering. Job's initial piety (chapter 1) gives way to protest (chapters 3-31), as he moves from accepting suffering to challenging God directly: 'I would speak to the Almighty, and I desire to argue my case with God' (13:3). The book's refusal to provide a comfortable answer - God speaks from the whirlwind not to explain Job's suffering but to overwhelm him with the mystery of creation - has been the most challenging biblical testimony for theodicy: it suggests that the question 'why?' may not be answerable within human categories.
Psalm 22:1 - 'My God, my God, why have you forsaken me? Why are you so far from saving me, so far from my cries of anguish?' - is the paradigmatic lament. Jesus's quotation of this verse from the cross (Matthew 27:46) makes it not merely a psychological expression of abandonment but a Christological statement: the incarnate Son takes on the experience of divine forsakenness, entering the darkest human experience of God's absence. Jurgen Moltmann's The Crucified God (1972) develops a theodicy centered on this verse: God is not the detached observer of suffering but the one who has suffered forsakenness from within.
Habakkuk 1:3 - 'Why do you make me look at injustice? Why do you tolerate wrongdoing? Destruction and violence are before me; there is strife, and conflict abounds' - voices the prophetic form of the problem of evil: not the suffering of individuals but the systemic injustice of social and political orders. Habakkuk cannot reconcile the God of justice with the continued prosperity of the wicked (the Babylonians) and the suffering of the righteous (Israel). God's answer - 'the righteous shall live by his faith' (2:4) - is not a philosophical theodicy but a call to trust in the longer arc of history.
The Logical Problem of Evil
J.L. Mackie's 'Evil and Omnipotence' (1955) formulated the logical problem: the existence of an omnipotent, omniscient, and omnibenevolent God is logically incompatible with the existence of evil. Any one of the three divine attributes, combined with evil, yields a contradiction: if God is all-powerful, God can eliminate evil; if all-knowing, God knows how to eliminate evil; if perfectly good, God wants to eliminate evil. Yet evil exists. Therefore God (as traditionally conceived) does not exist.
Alvin Plantinga's Free Will Defense (God, Freedom, and Evil, 1974) is the standard response to the logical problem. Plantinga argues that an omnipotent God cannot create free beings and guarantee that they will always choose good: genuine freedom includes the genuine possibility of choosing evil. A world containing genuinely free creatures who sometimes choose good is, for all we know, more valuable than a world of beings who always act correctly but without genuine freedom. The Free Will Defense establishes that the existence of moral evil is logically compatible with divine omnipotence and goodness - God could not create free beings without accepting the risk of evil.
Natural evil (earthquake, disease, famine) is not covered by the Free Will Defense; Plantinga's speculative response invokes the free will of demonic powers, but most philosophers of religion have not found this persuasive. John Hick's soul-making theodicy (Evil and the God of Love, 1966) argues that natural evil is permitted as a necessary condition of genuine moral development.
The Evidential Problem of Evil
William Rowe's 'The Problem of Evil and Some Varieties of Atheism' (1979) moved the debate from the logical to the evidential: even if evil is not logically incompatible with theism, its existence provides strong inductive evidence against theism. The sheer amount of suffering, the suffering of innocents (especially children), and the suffering of animals - who are not candidates for soul-making - makes it highly improbable that there is a God who could prevent all this suffering and chooses not to.
Stephen Wykstra developed 'CORNEA' (Condition of Reasonable Epistemic Access) to respond: we should not expect to be able to see the divine reasons for permitting suffering, because the gap between human and divine cognitive capacity is immense. What looks from our vantage point like pointless evil may have reasons entirely beyond our ken. This 'skeptical theism' has been the most influential response to the evidential problem.
The Crucified God
Moltmann's theodicy from the cross is the most theologically original contribution to the twentieth-century theodicy debate. Instead of defending God's goodness in the face of suffering, Moltmann argues that God has entered suffering from within: the crucifixion of Jesus is God's solidarity with all who suffer forsakenness. The theodicy question is not 'why does God permit this?' but 'where is God in this?' - and the Christian answer is 'in the midst of it, in the crucified Son.' This approach does not solve the philosophical problem but relocates it: the question shifts from the justification of God's ways to the redemption of suffering through God's participation in it.
The Protest Theodicy
Eliezer Berkovits's Faith After the Holocaust (1973) and Jewish philosophers influenced by the Holocaust have developed a 'protest theodicy': the correct response to evil is not philosophical justification but protest to God, in the mode of Job and of Elie Wiesel's Night. The tradition of hester panim (the 'hiding of God's face') in Jewish theology acknowledges the experience of divine absence while maintaining the address to God that is the structure of authentic prayer.
Key Passages
'Perhaps it is not proper for man to suffer for any reason, whether on account of human sin or out of love toward him. Perhaps the only answer to theodicy - a response that does not betray the question - is silence.' (Emmanuel Levinas, 'Useless Suffering,' trans. Hand)
'The suffering of a single child is enough to call into question the justice of God.' (Ivan Karamazov, in Dostoevsky's The Brothers Karamazov - the most powerful literary statement of the problem of evil)
Contemporary Relevance
The problem of evil has acquired new urgency in the context of the Holocaust, the Rwandan genocide, the AIDS pandemic, and the ongoing catastrophes of natural disaster and systemic injustice. Post-Holocaust theology - Berkovits, Fackenheim, Wiesel - has argued that the scale of the Holocaust requires new categories for theodicy that the traditional frameworks (Augustinian, Irenaean, Leibnizian) cannot provide. The question of whether theodicy is morally permissible - whether attempting to justify God's ways in the face of atrocity is itself a form of complicity with evil - is one of the most contested questions in contemporary philosophy of religion and theology. The biblical tradition of lament - Job, the Psalms, Habakkuk, Lamentations - continues to provide the most honest and philosophically durable response: the protest that addresses God rather than explaining God away.