Albert Barnes Commentary Deuteronomy 24:17-22

"Thou shalt not wrest the justice [due] to the sojourner, [or] to the fatherless, nor take the widow`s raiment to pledge; but thou shalt remember that thou wast a bondman in Egypt, and Jehovah thy God redeemed thee thence: therefore I command thee to do this thing. When thou reapest thy harvest in thy field, and hast forgot a sheaf in the field, thou shalt not go again to fetch it: it shall be for the sojourner, for the fatherless, and for the widow; that Jehovah thy God may bless thee in all the work of thy hands. When thou beatest thine olive-tree, thou shalt not go over the boughs again: it shall be for the sojourner, for the fatherless, and for the widow. When thou gatherest [the grapes of] thy vineyard, thou shalt not glean it after thee: it shall be for the sojourner, for the fatherless, and for the widow. And thou shalt remember that thou wast a bondman in the land of Egypt: therefore I command thee to do this thing." — Deuteronomy 24:17-22 (ASV)

Compare the marginal references. The motive assigned for these various acts of consideration is one and the same (Deuteronomy 24:18, 22).