Deuteronomy 24:18-22

But you shall remember that you were a slave in Egypt, and that the LORD your God redeemed you from there; therefore I am commanding you to do this thing. “When you reap your harvest in your field and have forgotten a sheaf in the field, you shall not go back to get it; it shall be for the alien, for the orphan, and for the widow, in order that the LORD your God may bless you in all the work of your hands. When you beat your olive tree, you shall not go over the boughs again; it shall be for the alien, for the orphan, and for the widow. “When you gather the grapes of your vineyard, you shall not go over it again; it shall be for the alien, for the orphan, and for the widow. You shall remember that you were a slave in the land of Egypt; therefore I am commanding you to do this thing.