Matthew 14:9

“And the king was sorry, etc.] As he might be upon many accounts; partly on account of John, whom, notwithstanding his freedom in reproving him, he had a respect; and partly on his own account, his conscience dictating to him that it was an evil action, and would leave a brand of perpetual infamy upon him; as also on account of the people, who were so much affected to John, lest they should make an insurrection, and rebel against him; and likewise, because it was reckoned an ill omen with the Romans, to take away life on that day they received their own; and therefore carefully abstained, on such days, from executions. Nevertheless for his oath’s sake; that he might not be guilty of perjury,…”

“See also Mark 6:21-29. But when Herod’s birthday was come Kings were accustomed to observe the day of their birth with much pomp, and commonly, also, by giving a feast to their principal nobility. See Genesis 40:20. Mark adds that this birthday was kept by making a supper to his “lords, high captains, and chief estates in Galilee;” that is to the chief men in office. “High captains” means, in the original, commanders of thousands, or of a division of 1,000 people. The daughter of Herodias - That is, “Salome,” her daughter by her former husband. This was a violation of all the rules of modesty and propriety. One great principle of all eastern nations is to keep their females from public view.…”

“And the king was sorry - Knowing that John was a good man. Yet for the oath's sake - So he murdered an innocent man from mere tenderness of conscience. Matthew 14:10”

“the king: Mat 14:1; Mar 6:14 sorry: Mat 14:5, Mat 27:17-26; Dan 6:14-16; Mar 6:20, Mar 6:26; Luk 13:32; Joh 19:12-16; Act 24:23-27, Act 25:3-9 the oath's: Num 30:5-8; Jdg 11:30, Jdg 11:31, Jdg 11:39, Jdg 21:1, 7-23; Sa1 14:24, Sa1 14:28, Sa1 14:39-45, Sa1 25:22; Sa1 25:32-34, Sa1 28:10; Kg2 6:31-33; Ecc 5:2 Matthew 14:10”