A hundred Philistine foreskins. Saul has his servants tell David, "The king desires no marriage present except a hundred foreskins of the Philistines" (1 Samuel 18:25). The text says why: Saul planned to make David fall by the hand of the Philistines. David goes out with his men instead, kills a hundred Philistines, brings the foreskins "in full number," and marries Michal (18:27).
A marriage present, the bridewealth, was set by the bride's father and paid by the groom. All through Samuel the Philistines are called "the uncircumcised," and the note in the New Oxford Annotated Bible reads Saul's price as dark humor: the proof he asks for can only be cut from a hundred dead Philistines.
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