John Gills Exposition of the Bible Commentary - Proverbs 14:21
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... read more
Matthew Henry's Complete Commentary - Proverbs 14:21
See here how men's character and condition are measured and judged of by their conduct towards their poor neighbours. 1. Those that look upon them with contempt have here assigned them a bad character, and their condition will be accordingly: He that despises his neighbour because he is low in the world, because he is of a mean extraction, rustic education, and makes but a mean figure, that thinks it below him to take notice of him, converse with him, or concern himself about him, and sets him... read more