One of the central doctrines of Christianity is the Atonement, which in a broad sense concerns how humans, with their sinful nature, are reconciled to God. The Atonement thus fundamentally involves the forgiveness of sins. One problem, then, is why Jesus’ crucifixion and death occur given that they are unnecessary for the forgiveness of sins: God, who is both omnipotent and the subject offended against by sins, could easily have forgiven sins without requiring any such sacrifice. A more specific problem that I have, and one that is in my view more important, is that the purpose of the Atonement stands in conflict with the means God is supposed to have chosen to carry it out. In order for the Atonement to occur as it “should”, it seems necessary that some people sin. For if God deems it appropriate for Jesus to endure suffering and death, who is to inflict this on him? Why would God require that someone—such as Judas Iscariot—commit such a horrible sin in order to bring God’s plan to fruition? This worry is especially troublesome because the purpose of the Atonement is to forgive sin. Taking the above example, one may reply that God did not, as I imply, force Judas to do what he did; Judas betrayed Jesus of his own free will. Yet if no one was under any compulsion to bring about Jesus’ death on the cross, it is possible that none should have done so. But what then? If everyone had “done the right thing”, so that no one betrayed or tried to harm Jesus, would Jesus have caused himself to endure suffering and death? If the answer is no—and it seems to me overwhelmingly probable that it would be—would God then choose some other means of forgiving sins? I think so, but then we again face the problem of why God would not have chosen a means of Atonement that did not involve the commission of sin in the first place.
In conclusion, the doctrine of the Atonement is not without its problems. While these difficulties may not be insurmountable, I think they are worth taking seriously.
 For the sake of argument, I am assuming that free will is incompatible with determinism.