unto Abraham, &c. All three mentioned together here as equally subjects of the oath of Jehovah. Compare Genesis 50:24.
Related Commentaries of Numbers 32:11
Numbers 32:11
11 Surely none of the men that came up out of Egypt, from twenty years old and upward, shall see the land which I sware unto Abraham, unto Isaac, and unto Jacob; because they have not whollyb followed me: