There are cases of Bible writers forgetting/overlooking writings of fellow Bible writers. For example, if a liar is caught, he should be treated as impurity in the society, and should be cut off from the society so that it may serve as a lesson for others: “If a malicious witness takes the stand to accuse someone of a crime, the two people involved in the dispute must stand in the presence of the Lord before the priests and the judges who are in office at the time. The judges must make a thorough investigation, and if the witness proves to be a liar, giving false testimony against a fellow Israelite, then do to the false witness as that witness intended to do to the other party. You must purge the evil from among you. The rest of the people will hear of this and be afraid, and never again will such an evil thing be done among you. Show no pity: life for life, eye for eye, tooth for tooth, hand for hand, foot for foot.”(Deuteronomy 19:16-21)
According to this Law, it is Satan (not Jesus Christ) that should have been crucified. But it seems Paul went against this Law, and theorized that killing an innocent man would remove the sins of the world.