Deuteronomy 24:17-19

17Thou shalt not pervert the judgment of the stranger, [or] of the fatherless; and thou shalt not take in pledge a widow's garment.

18And thou shalt remember that thou wast a bondman in Egypt, and that Jehovah thy 1God redeemed thee from thence; therefore I command thee to do this thing.

19When thou reapest thy harvest in thy field, and forgettest a sheaf in the field, thou shalt not return to fetch it; it shall be for the stranger, for the fatherless, and for the widow; that Jehovah thy 2God may bless thee in all the work of thy hands.