Vicarious atonement

In the world today we are of course alarmed and fascinated by the huge numbers of Muslim men (and some women) who both commit and avoid the Islamic sin of suicide by blowing up at least one religious enemy along with them in an act of blessed martyrdom. But even more amazing, really, in its sheer irrationality, is that ancient act of vicarious atonement for which Christians can be so abjectly thankful. From Christopher Hitchens's book God Is Not Great:

Atonement

Previous sacrifices of humans, such as the Aztec and other ceremonies from which we recoil, were common in the ancient world and took the form of propitiatory murder. An offering of a virgin or an infant or a prisoner was assumed to appease the gods: once again, not a very good advertisement for the moral properties of religion. "Martyrdom," or a deliberate sacrifice of oneself, can be viewed in a slightly different light, though when practiced by the Hindus in the form of suttee, or the strongly suggested "suicide" of widows, it was put down by the British in India for imperial as much as for Christian reasons. Those "martyrs" who wish to kill others as well as themselves, in an act of religious exaltation, are viewed more differently still: Islam is ostensibly opposed to suicide per se but cannot seem to decide whether to condemn or recommend the act of such a bold shahid.
      However, the idea of a vicarious atonement, of the sort that so much troubled even C. S. Lewis, is a further refinement of the ancient superstition. Once again we have a father demonstrating his love by subjecting a son to death by torture, but this time the father is not trying to impress god. He is god, and he is trying to impress humans. Ask yourself the question: how moral is the following? I am told of a human sacrifice that took place two thousand years ago, without my wishing it and in circumstances so ghastly that, had I been present and in possession of any influence, I would have been duty-bound to try and stop it. In consequence of this murder, my own manifold sins are forgiven me, and I may hope to enjoy everlasting life. [pp. 208-209]