Genesis 21:27-30

27So Abraham brought some sheep and some cows and he gave them to Abimelech. The two men made a promise to help each other.

28Abraham took seven female lambs from the sheep. He put them in a different place from the other animals.

29Abimelech asked Abraham, ‘Why have you put these seven lambs in a different place?’

30Abraham replied, ‘You must accept these seven lambs as a gift from me. That will show that you agree that I dug this well. Everyone will know that it belongs to me.’