He that despiseth his neighbor sinneth - To despise a man because he has some natural blemish is unjust, cruel, and wicked. He is not the author of his own imperfections; they did not occur through his fault or folly; and if he could, he would not retain them. It is, therefore, unjust and wicked to despise him for what is not his fault, but his misfortune.
But he that hath mercy on the poor - Who reproaches no man for his poverty or scanty intellect, but divides his bread with the hungry - happy is he; the blessing of God, and of them that were ready to perish, shall come upon him.

He that despiseth his neighbour sinneth,.... He that despiseth his neighbour in his heart, speaks slightly of him, overlooks him, is not friendly to him, will neither converse with him, nor relieve him in his necessity; for it seems to be understood of his poor neighbour; and so the Septuagint and Arabic versions render it, "he that despiseth the poor"; that despises him for his poverty; because of his pedigree and education, and the low circumstances he is in; or on account of his weakness and incapacity, or any outward circumstance that attends him; such an one sins very greatly, is guilty of a heinous sin; and he will be reckoned and dealt with as a sinner, and be condemned and punished, and so be unhappy and miserable;
but he that hath mercy on the poor, happy is he; or,
"that gives to the poor,''
as the Targum; who has compassion on him in his distress, and shows it by relieving him: he that shows favour to the meek and humble ones, as the word (s) may be rendered, and as they generally are that are in affliction and poverty, for these tend to humble men; and such who regard them in their low estate are "happy" or blessed; they are blessed in things temporal and spiritual, and both here and hereafter; see Psalm 41:1.
(s) "modestorum", Montanus, Mercerus; "mansuetos", Cocceius.

To despise a man for his employment or appearance is a sin.

For such contempt of the poor is contrasted as sinful with the virtuous compassion of the good.

21 Whoever despiseth his neighbour committeth sin;
But whoever hath compassion on the suffering - blessings on him!
One should regard every human being, especially such as God has placed near to him, as a being having the same origin, as created in the image of God, and of the same lofty destination, and should consider himself as under obligation to love him. He who despiseth his neighbour (write בּז with Metheg, and vid., regarding the constr. with dat. object. Proverbs 6:30, cf. Proverbs 11:12; Proverbs 13:13) sins in this respect, that he raises himself proudly and unwarrantably above him; that the honour and love he shows to him he measures not by the rule of duty and of necessity, but according to that which is pleasing to himself; and in that he refuses to him that which according to the ordinance of God he owes him. In Proverbs 14:21 the Chethı̂b עניּים and the Kerı̂ ענוים (vid., at Psalm 9:13) interchange in an inexplicable way; עני is the bowed down (cf. Arab. ma'nuww, particularly of the prisoner, from 'ana, fut. ya'nw, to bow, bend), ענו (Arab. 'anin, with the art. âl'niy, from the intrans. 'aniya, to be bowed down) the patient bearer who in the school of suffering has learned humility and meekness. One does not see why the Kerı̂ here exchanges that passive idea for this ethical one, especially since, in proving himself to be מחונן (compassionate) (for which elsewhere the part. Kal חונן, Proverbs 14:31; Proverbs 19:17; Proverbs 28:8), one must be determined only by the needy condition of his neighbour, and not by his (the neighbour's) moral worthiness, the want of which ought to make him twofold more an object of our compassion. All the old translators, from the lxx to the Venet. and Luther, on this account adopt the Chethı̂b.

Despiseth - That does not pity and relieve the poor.