Honoureth him - i. e., God, who is the Maker of poor and rich alike.

He that oppresseth the poor reproacheth his Maker - Because the poor, or comparatively poor, are, in the order of God, a part of the inhabitants of the earth; and every man who loves God will show mercy to the poor, for with this God is peculiarly delighted. The poor have we ever with us, for the excitement and exercise of those benevolent, compassionate, and merciful feelings, without which men had been but little better than brutes.

He that oppresseth the poor reproacheth his Maker,.... That does him any injury, either by scoffing at him, and reproaching him for his poverty; or by vexatious law suits; or by withholding from him his wages; or not giving him that relief which he ought: such an one not only injures the poor man; but reproaches God that made him, not only a man, but a poor man; and who is the Maker of the rich man also, Proverbs 22:2;
but he that honoureth him hath mercy on the poor; he that is desirous of honouring God, and glorifying him, will give of his substance to the poor; having compassion on him in his necessitous circumstances, will relieve him; and in so doing he honours God, whose image the poor man bears, and who has commanded him so to do. The words may be rendered, "he that hath mercy on the poor honoureth him"; that is, his Maker: so the Targum,
"he that hath mercy on him that suffers injury honoureth him.''

To oppress the poor is to reproach our Creator.

reproacheth his Maker--who is the God of such, as well as of the rich (Proverbs 22:2; Job 31:15; and specially 1-Samuel 2:8; Psalm 113:7).

31 He who oppresseth the poor reproacheth his Maker;
And whosoever is merciful to the poor, it is an honour to him.
Line first is repeated in Proverbs 17:5 somewhat varied, and the relation of the idea in 31b is as Proverbs 19:17, according to which וּמכבּדו is the predicate and חונן אביון the subject (Symmachus, Targ., Jerome, Venet., Luther), not the reverse (Syr.); חונן is thus not the 3 per. Po. (lxx), but the part. Kal (for which 21b has the part. Po. מחונן). The predicates חרף עשׂהוּ (vid., regarding the perf. Gesen. 126, 3) and ומכבדו follow one another after the scheme of the Chiasmus. עשׁק has Munach on the first syllable, on which the tone is thrown back, and on the second the העמדה sign (vid., Torath Emeth, p. 21), as e.g., פּוטר, Proverbs 17:14, and אהב, Proverbs 17:19. The showing of forbearance and kindness to the poor arising from a common relation to one Creator, and from respect towards a personality bearing the image of God, is a conception quite in the spirit of the Chokma, which, as in the Jahve religion it becomes the universal religion, so in the national law it becomes the human. Thus also Job 31:15, cf. Proverbs 3:9 of the Epistle of James, which in many respects has its roots in the Book of Proverbs. Matthew 25:40 is a New Testament side-piece to 31b.

His maker - Whose image the poor man bears, by whose providence he is made poor, and who hath declared himself to be their protector and avenger.