Genesis 31:51-53

New International Reader's Version

⁵¹ Laban also said to Jacob, “Here is this pile of stones. And here is this stone I’ve set up. I’ve set them up between you and me. ⁵² This pile is a witness. And this stone is a witness. They are witnesses that I won’t go past this pile to harm you. And they are witnesses that you won’t go past this pile and this stone to harm me. ⁵³ The God of Abraham and Nahor is also the God of their father. May their God decide which of us is right.”

So Jacob made a promise using the name of the God his father Isaac worshiped.