I have been in a few face-to-face debates with Muslims, and all of them were polite and respectful. One question from my Muslim friends kept popping up, however: "Why did Jesus have to die on the cross for our sins? If we sin, God just forgives! He does not need for someone to take our place." Muslims have told me that this substitutionary sacrifice is actually very unfair of God. God would never let a righteous man die for the guilty. They illustrate it this way: "Would God allow an innocent baby to die for the crimes of murderers? Of...