2 Samuel 21:1-3

Then there was a famine in the days of David three years, year after year; and David enquired of the LORD. And the LORD answered, It is for Saul, and for his bloody house, because he slew the Gibeonites. And the king called the Gibeonites, and said unto them; (now the Gibeonites were not of the children of Israel, but of the remnant of the Amorites; and the children of Israel had sworn unto them: and Saul sought to slay them in his zeal to the children of Israel and Judah.) Wherefore David said unto the Gibeonites, What shall I do for you? and wherewith shall I make the atonement, that ye may bless the inheritance of the LORD?