1 Samuel 18:25

(25) An hundred foreskins.—Wordsworth’s note here, which he derives from Theodoret, is curious. Foreskins! why not heads? Here is a sign of Saul’s suspicious and malignant spirit. He, judging for himself, impiously suspects that David would go forth and destroy some of the Israelites—Saul’s own subjects—as he himself desired to destroy David, his own deliverer; and the foreskins were required as a proof that they who were killed were not Israelites. Josephus, however, with a strange exaggeration, mentions 600 heads as the price of Michal.