Rather, And if thy brother (an Israelite) becomes poor and falls into decay with thee, thou shalt assist him and let him live with thee like a resident foreigner. He was not to be regarded as an outcast, but was to be treated with the same respect and consideration as a resident foreigner who, like him, could possess no land, but could accumulate property and live in comfort as a free man. See Leviticus 16:29 note.

And if thy brother be waxen poor, and (r) fallen in decay with thee; then thou shalt relieve him: [yea, though he be] a stranger, or a sojourner; that he may live with thee.
(r) In Hebrew it is, if his hand shake: meaning if he stretch forth his hand for help as one in misery.

And if thy brother be waxen poor,.... An Israelite, as Aben Ezra, be reduced to a low estate, through afflictions in body, or in family, or through losses in trade, or want of business, or through one providence or another:
and fallen in decay with thee; in his worldly substance: or "his hand wavers", or "fails" (p); so that he cannot support himself and his family, has not a sufficiency, or it is not in the power of his hands to do it; and it is not owing to sloth and negligence, but to unavoidable want and necessity:
then thou shalt relieve him; not merely by sympathizing with him, but by communicating to him, and distributing to his necessities; holding him up that he may not utterly fall, and strengthening his hands, that he may have a supply for his present wants:
yea, though he be a stranger or a sojourner; whether a proselyte of righteousness, who is circumcised, and in all things conforms to the true religion; or a proselyte of the gate, who takes it upon him not to worship idols, and eat things that die of themselves, as Jarchi notes:
that he may live with thee; continue in the land of Canaan, and not be obliged to quit it, and be laid under temptations of apostatizing from the true religion professed by him, and so far as he is come into it, which would bring a worse death than corporeal upon him; or that he may have a livelihood in some tolerable manner at least, and even live comfortably and cheerfully.
(p) "et nutaverit manus ejus", Montanus, Vatablus, Fagius; "vacillabit", Junius & Tremellius, Piscator.

Poverty and decay are great grievances, and very common; the poor ye have always with you. Thou shalt relieve him; by sympathy, pitying the poor; by service, doing for them; and by supply, giving to them according to their necessity, and thine ability. Poor debtors must not be oppressed. Observe the arguments here used against extortion: "Fear thy God." Relieve the poor, "that they may live with thee;" for they may be serviceable to thee. The rich can as ill spare the poor, as the poor can the rich. It becomes those that have received mercy to show mercy.

if thy brother be waxen poor, . . . relieve him--This was a most benevolent provision for the poor and unfortunate, designed to aid them or alleviate the evils of their condition. Whether a native Israelite or a mere sojourner, his richer neighbor was required to give him food, lodging, and a supply of money without usury. Usury was severely condemned (Psalm 15:5; Ezekiel 18:8, Ezekiel 18:17), but the prohibition cannot be considered as applicable to the modern practice of men in business, borrowing and lending at legal rates of interest.

"If thy brother (countryman, or member of the same tribe) becomes poor, and his hand trembles by thee, thou shalt lay hold of him;" i.e., if he is no longer able to sustain himself alone, thou shalt take him by the arm to help him out of his misfortune. "Let him live with thee as a stranger and sojourner." וחי introduces the apodosis (see Ges. 126, note 1).

A sojourner - Understand it of proselytes only, for of other strangers they were permitted to take usury, Deuteronomy 23:20.