For Herod himself had ordered that John be arrested and bound and imprisoned, on account of his brother Philip’s wife Herodias, whom Herod had married.
Textus Receptus (TR) - Mark 6:17 >Αὐτὸς γὰρ ὁ Ἡρῴδης ἀποστείλας ἐκράτησε τὸν Ἰωάννην, καὶ ἔδησεν αὐτὸν ἐν τῇ φυλακῇ, διὰ Ἡρῳδιάδα τὴν γυναῖκα Φιλίππου τοῦ ἀδελφοῦ αὐτοῦ, ὅτι αὐτὴν ἐγάμησεν.