Joshua 9:18-20
9:18 The Israelites did not attack them because the leaders of the community had sworn an oath to them in the name of the Lord God of Israel. The whole community criticized the leaders,
9:19 but all the leaders told the whole community, “We swore an oath to them in the name of the Lord God of Israel. So now we can’t hurt them!
9:20 We must let them live so we can escape the curse attached to the oath we swore to them.”