The Gibeonites were not Israelites but rather a remnant of the Amorites. The Israelites had taken an oath concerning them, but Saul had tried to kill them in his zeal for the Israelites and Judah. So David summoned the Gibeonites and spoke to them.
He despised the oath by breaking the covenant. He did all these things even though he gave his hand in pledge. He will not escape!”Therefore, this is what the Lord God says:“ As I live, I will bring down on his head My oath that he despised and My covenant that he broke.