Aristotle argues that God cannot suffer, for a suffering God would be a God subject to change. To Aristotle, the perfection of God is located in God's changelessness. The logic proceeds that if God were to decrease in perfection, obviously God would cease to be perfect, and therefore, cease to be God. Moreover, if God were to increase in perfection, such increase would indicate that God had not previously been complete in perfection, thus negating God's supposed divinity. So then, to Aristotle, any "passion" (change) on God's behalf is effectively self-negating. Although I appreciate the power of Aristotle's argument concerning the necessary immutability of God, at the end of the day I am unconvinced. It seems fairly arbitrary to define perfection as 'changelessness.' While I do understand Aristotle's rationale, his argument seems blind to the counter that in preserving God's unqualified "changelessness," one has also effectively stripped God of any ability to act, thus reducing God to a benign deity lost in perpetual and eternal self-contemplation.

Historically, the Church has adopted the categories provided by Aristotle, affirming that God is "impassable." For centuries, Christian theology has located the suffering of Christ within the human nature of Christ while concomitantly affirming the impassability of Christ's divine nature. An obvious result of this has been a bifurcation between the divine and human natures of Christ, leading to a potentially restricted and somewhat disconnected conception of the relationship of the divine to human nature and experience. Despite the central place which the doctrine of the impassability of God has enjoyed in historical Christian thought, recent theological exploration has reconsidered the categories provided by Aristotle, rejecting them in favor of the biblical witness and theological necessity of engaging the whole person–not singular human nature–of Christ in the suffering endured on the cross. Seminal in recent scholarship has been The Crucified God in which Moltmann describes not only the suffering endured by the Son on the cross, but also the suffering which the Father experienced in relation to the death and rejection of the Son at the hands of sinful humanity.

Now, to get right down to the question, I believe the answer is "Yes," God does suffer. I think this is necessitated by the Christian proclamation that "God is love." For example, a great definition of love (at least in my mind) is that of complete self-giving, a definition which is poignantly displayed in Christ's ultimate self-giving of himself to humanity and to the Father's will in the cross. However, this "self-giving" is total, in that one gives oneself to others while concomitantly taking into one's own person the totality of the other.

Therefore, if Christ truly represents the total self-giving (love) of God in being made "sin" for us, this means that in giving himself to us, Christ has concurrently encountered, in his very person, the full depths of human sinfulness. As Paul Jensen wonderfully point out, in this self-giving, Christ "[absorbs] into his own being the consequences of human sin."* This encounter with human sinfulness cannot simply be located in the "human" side of Christ. Rather, as the consequence of sin is death (separation from God), it is clear that Christ, in the fullness of his person, is subject to the full judgment of sin and dies, feeling the unbearable weight of separation from the Father.

However, despite Aristotle's fear that a "passioned" deity would be self-contradictory and negating, the suffering of Christ is actually the means by which the fullness of God's love is revealed to humanity. Although Christ is indeed subject to the full wrath and power of the consequences of sinfulness, he is not defeated. Moreover, even though Christ has "absorbed into his own being the consequence of human sin," this very act of self-giving love is the means by which sin and death are overcome, their powers exhausted in his very person.

In this answer, I have perhaps strayed a bit too far into Atonement theology. However, I believe this is necessary for, as Luther powerfully pointed out, God is not to be known in abstraction. Rather, the cross is the paradigm through which we are to approach the knowledge of God, for it is through the suffering and death of Christ that the true "face" of God is revealed. Therefore, this "theology of the cross" compels us to rethink the question not on the basis of whether a "suffering God" is possible, but rather because this is precisely the way in which God has revealed the divine nature, purpose and love. For a world of people separated from the only source of life and suffering at the hands of evil people, systems of oppression and the capriciousness of the physical world, the question of whether or not God can suffer is most prescient. After all, within this question lies the only hope of human salvation.

*Paul Jensen, "Forgiveness and Atonement," Scottish Journal of Theology 46 (1993): 141-159 at 154.