Deuteronomy 24:19-22
19
When you reap your harvest in your field, and have forgot a sheaf in the field, you shall not go again to get it: it shall be for the foreigner, for the fatherless, and for the widow; that Yahweh your God may bless you in all the work of your hands.
20
When you beat your olive tree, you shall not go over the boughs again: it shall be for the foreigner, for the fatherless, and for the widow.
21
When you gather [the grapes of] your vineyard, you shall not glean it after yourselves: it shall be for the foreigner, for the fatherless, and for the widow.
22
You shall remember that you were a bondservant in the land of Egypt: therefore I command you to do this thing.