Genesis 21:22-24

And it came to pass at that time that Abimelech and Phichol, the commander of his army, spoke to Abraham, saying, “God is with you in all that you do. Now therefore, swear to me by God that you will not deal falsely with me, with my offspring, or with my posterity; but that according to the kindness that I have done to you, you will do to me and to the land in which you have dwelt.” And Abraham said, “I will swear.”