Abimelech

"(To Abraham, after discovering that Sarah is his wife) And Abimelech called Abraham and said to him, “What have you done to us? How have I offended you, that you have brought on me and on my kingdom a great sin? You have done deeds to me that ought not to be done.”"

"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.”"

"So Abraham took sheep and oxen and gave them to Abimelech, and the two of them made a covenant. [...] herefore he called that place Beersheba, because the two of them swore an oath there."