Did David pay a hundred Philistine foreskins for Michal, or two hundred?

Both numbers are right, because they answer different questions. A hundred was the price Saul set: “The king desireth not any dowry, but an hundred foreskins of the Philistines” (1 Samuel 18:25). Saul hoped that David would be killed trying to pay it. David brought double. He killed two hundred men and handed over their foreskins “in full tale”, that is, in full number, so that no one could say the price had not been met (18:27).

Years later, when David demanded his wife back from Saul’s son Ish-bosheth, he was stating a legal claim. He named the bride-price that had been agreed for Michal, the hundred foreskins Saul had required, because that was what made her his lawful wife and bound Saul’s house to its side of the bargain (2 Samuel 3:14). The second hundred had been a gift beyond the terms, and there was no reason to mention it. Gill and Ellicott both explain the verse this way: a hundred was required, two hundred were given, and only the required number is named.

A hundred in both places

The Greek Septuagint reads ‘a hundred men’ in 1 Samuel 18:27 too, and Adam Clarke thought a hundred was therefore the original reading there. The Hebrew text reads two hundred, and the Greek may simply have brought the verse into line with verse 25 and 2 Samuel 3:14. On either reading the passages agree.