Genesis 47:23-31

Then Joseph said to the people, “Look, today I have bought you and your land for Pharaoh; now, here is seed for you, and you shall plant the land. At harvest time [when you reap the increase] you shall give one-fifth of it to Pharaoh, and four-fifths will be your own to use for seed for the field and as food for you and those of your households and for your little ones.” And they said, “You have saved our lives! Let us find favor in the sight of my lord, and we will be Pharaoh’s servants.” And Joseph made it a law over the land of Egypt—valid to this day—that Pharaoh should have the fifth part [of the crops]; only the land of the priests did not become Pharaoh’s. Now [the people of] Israel lived in the country of Egypt, in [the land of] Goshen, and they gained possessions and acquired property there and were fruitful and multiplied greatly. And Jacob lived in the land of Egypt seventeen years; so the length of Jacob’s life was a hundred and forty-seven years. And when the time drew near for Israel to die, he called his son Joseph and said to him, “If now I have found favor in your sight, please put your hand under my thigh and [promise to] deal loyally and faithfully with me. Please do not bury me in Egypt, but when I lie down with my fathers [in death], you will carry me out of Egypt and bury me in their burial place [at Hebron in the cave of Machpelah].” And Joseph said, “I will do as you have directed.” Then he said, “Swear to me [that you will do it].” So he swore to him. Then Israel (Jacob) bowed in worship at the head of the bed.