Genesis 47:24-26 Modern English Version (MEV)
24 At the harvest, you must give a fifth part to Pharaoh and four parts will be your own, as seed for the field and for your food and for those of your households and for food for your little ones.”
25 They said, “You have saved our lives. Let us find grace in the sight of my lord, and we will be Pharaoh’s slaves.”
26 So Joseph made it a law over the land of Egypt to this day, that Pharaoh should have the fifth part, except from the land of the priests, which did not become Pharaoh’s.