Jerome: "The old history tells us, that Philip the son of Herod the greater, the brother of this Herod, had taken to wife Herodias daughter of Aretas, king of the Arabs; and that he, the father-in-law, having afterwards cause of quarrel with his son-in-law, took away his daughter, and to grieve her husband gave her in marriage to his enemy Herod. John the Baptist therefore, who came in the spirit and power of Elias, with the same authority that he had exerted over Ahab and Jezebel, rebuked Herod and Herodias, because that they had entered into unlawful wedlock; it being unlawful while the own brother yet lives to take his wife. He preferred to endanger himself with the King, than to be forgetful of the commandments of God in commending himself to him."[2]
Chrysostom: "Yet he speaks not to the woman but to the husband, as he was the chief person."[2]
Glossa Ordinaria: " And perhaps he observed the Jewish Law, according to which John forbade him this adultery. And desiring to kill him, he feared the people."[2]
^John MacEvilly, An Exposition of the Gospel of St. John consisting of an analysis of each chapter and of a Commentary critical, exegetical, doctrinal and moral, Dublin Gill & Son 1879.