Albert Barnes Commentary Proverbs 7:21

"With her much fair speech she causeth him to yield; With the flattering of her lips she forceth him along." — Proverbs 7:21 (ASV)

Fair speech - The Hebrew word is usually translated “doctrine,” or “learning” (Proverbs 1:5; Proverbs 4:2; Proverbs 9:9); possibly it is used here in keen irony.