There is a specific kind of warfare laid down in the Bible which we can only call genocide."
It is called herem, and it means total annihilation. Consider the Book of 1 Samuel, when God instructs King Saul to attack the Amalekites: "And utterly destroy all that they have, and do not spare them," God says through the prophet Samuel. "But kill both man and woman, infant and nursing child, ox and sheep, camel and donkey."
When Saul failed to do that, God took away his kingdom.
"In other words," Jenkins says, "Saul has committed a dreadful sin by failing to complete genocide. And that passage echoes through Christian history. It is often used, for example, in American stories of the confrontation with Indians — not just is it legitimate to kill Indians, but you are violating God's law if you do not."
Jenkins notes that the history of Christianity is strewn with herem. During the Crusades in the Middle Ages, the Catholic popes declared the Muslims Amalekites. In the great religious wars in the 16th, 17th and 19th centuries, Protestants and Catholics each believed the other side were the Amalekites and should be utterly destroyed.
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