Tim Keller, in The Reason for God, lays out an incredible picture of the spiritual suffering that Christ had to endure on the cross for our redemption. This excerpt is from the third chapter on how a good God could allow suffering and evil.
"The Son of God was not created but took part in creation and has lived throughout all eternity 'in the bosom of the father' (John 1:18)-- that is, in a relationship of absolute intimacy and love. But at the end of his life he was cut off from the Father.
There may be no great inner agony than the loss of a relationship we desperately want. If a mild acquaintance turns on you, condemns and criticizes you, and says she never wants to see you again, it is painful. If someone you're dating does the same thing, it is qualitatively more painful. But if your spouse does this to you, or if one of your parents does this to you when you're still a child, the psychological damage is infinitely worse.
We cannot fathom, however, what it would be like to lose not just a spousal love or parental love that has lasted several years, but the infinite love of teh Father that Jesus had from all eternity. Jesus's sufferings would have been eternally unbearable. Christian theology has always recongized that Jesus bore, as the subsitute in our place, the endless exclusion from God that he human race has merited. . . . The death of Jesus was qualititatively different form any other death. The physical pain was nothing comared to the spiritual experience of cosmin abandonment. . . . On the Cross he went beyond even the worst human suffering and experienced cosmic rejection and pain that exceeds ours as infintely as his knowledge and power exceeds ours. . . . The Bible says that Jesus came on a rescue mission for creation. He has to pay for our sins so taht someday he can end evil suffering without ending us" (Keller 29-30).
