Genesis

²⁷So Abraham took sheep and oxen and gave them to Abimelech, and the two men made a league or covenant. ²⁸Abraham set apart seven ewe lambs of the flock, ²⁹And Abimelech said to Abraham, What do these seven ewe lambs which you have set apart mean? ³⁰He said, You are to accept these seven ewe lambs from me as a witness for me that I dug this well. ³¹Therefore that place was called Beersheba [well of the oath], because there both parties swore an oath. ³²Thus they made a covenant at Beersheba; then Abimelech and Phicol the commander of his army returned to the land of the Philistines. ³³Abraham planted a tamarisk tree in Beersheba and called there on the name of the Lord, the Eternal God.