Genesis 21:30-34 New King James Version (NKJV)

30. And he said, “You will take these seven ewe lambs from my hand, that they may be my witness that I have dug this well.”

31. Therefore he called that place Beersheba, because the two of them swore an oath there.

32. Thus they made a covenant at Beersheba. So Abimelech rose with Phichol, the commander of his army, and they returned to the land of the Philistines.

33. Then Abraham planted a tamarisk tree in Beersheba, and there called on the name of the Lord, the Everlasting God.

34. And Abraham stayed in the land of the Philistines many days.

Genesis 21