You shall remember that you were a slave in the land of Egypt, and the LORD your God redeemed you; therefore I command you this thing today.
Deuteronomy 15:15
Surrounding context
15:14 you shall supply him liberally from your flock, from your threshing floor, and from your winepress. From what the LORD has blessed you with, you shall give to him.
15:15 You shall remember that you were a slave in the land of Egypt, and the LORD your God redeemed you; therefore I command you this thing today.
15:16 And if it happens that he says to you, "I will not go away from you,' because he loves you and your house, since he prospers with you,