2 Samuel 21:1-3

Now there was a famine in the days of David for three years, year after year; and David sought the presence of the LORD. And the LORD said, “It is for Saul and his bloody house, because he put the Gibeonites to death.” So the king called the Gibeonites and spoke to them (now the Gibeonites were not of the sons of Israel but of the remnant of the Amorites, and the sons of Israel made a covenant with them, but Saul had sought to kill them in his zeal for the sons of Israel and Judah). Thus David said to the Gibeonites, “What should I do for you? And how can I make atonement that you may bless the inheritance of the LORD?”