Joshua 9

2. To shed the blood of another contrary to promise. Thus after the princes of Israel had sworn to the Gibeonites that they should live (Joshua 9:15), Saul slew them (2 Samuel 21:1). Here were two sins twisted together, breach of oath and murder.

And therefore the Author to the Hebrews says, that God, to make known the stableness of his counsel promised,bound himself with an oath; that by two immutable things (to wit, God's promise, and oath) we might have strong consolation: so that an oath binds a man double to the per…