(Exodus 13:19) "For hashbea hishbia the children of Israel": He (Joseph) had made them (his brothers) swear ("hashbea") that they would beswear ("hishbia") their children. R. Nathan says: Why did Joseph beswear his brothers and not his sons (to bury him in Canaan)? He reasoned: If I beswear my sons (to do this), the Egyptians will not permit them. And if they would say: But our father (Joseph) brought up his father (Jacob), immediately (upon his death), they would answer: Your father was a king (and could do as he wished.) Therefore, he beswore his brothers and not his sons.