Hebrews 6:13

When God gave his promise to Abraham, since there was no one greater by whom he could swear, he swore by himself.

Luke 1:54-55

He has stretched out his hand to his servant Israel, Ever mindful of his mercy

Treasury of Scripture Knowledge

Summary

Remember Abraham, Isaac, and Israel, thy servants, to whom thou swarest by thine own self, and saidst unto them, I will multiply your seed as the stars of heaven, and all this land that I have spoken of will I give unto your seed, and they shall inherit it for ever.

To whom

Bible References

To whom

Hebrews 6:13
When God gave his promise to Abraham, since there was no one greater by whom he could swear, he swore by himself.