I have heard many sermons about the physical pain of death by crucifixion. I've heard graphic descriptions of the nails and the thorns. Surely the physical agony of crucifixion was a ghastly thing. But there were thousands who died on crosses and may have had more painful deaths than that of Christ. But only one person has ever received the full measure of the curse of God while on a cross. I doubt that Jesus was even aware of the nails and the spear - he was so overwhelmed by the outer darkness. On the cross Jesus was in the reality of hell. He was totally bereft of the grace and the presence of God, utterly separated from all blessedness of the Father. He became a curse for us so that we someday will be able to see the face of God. So that the light of his countenance might fall upon us, God turned his back on his Son. No wonder Christ screamed. He screamed from the depth of his soul. How long did he have to endure it? We don't know, but a second of it would have been of infinite value.
Finally, Jesus cried, "It is finished." (John 19:30) It was over. What was over? His life? No. It was the forsakenness that ended. The curse was finished.
From "Cursed" by R.C. Sproul (page 95) in Jesus, Keep Me Near The Cross edited by Nancy Guthrie.