Albert Barnes Commentary Proverbs 15:26

"Evil devices are an abomination to Jehovah; But pleasant words [are] pure." — Proverbs 15:26 (ASV)

Some prefer the marginal reading and render it: “Words of pleasantness are pure.” Gracious words are to God as a pure, acceptable offering, the analogy being drawn from the Levitical ritual, and the word “pure” in a partly ceremonial sense .