Mark 6:17-20 NIV

[17] For Herod himself had given orders to have John arrested, and he had him bound and put in prison. He did this because of Herodias, his brother Philip’s wife, whom he had married. [18] For John had been saying to Herod, “It is not lawful for you to have your brother’s wife.” [19] So Herodias nursed a grudge against John and wanted to kill him. But she was not able to, [20] because Herod feared John and protected him, knowing him to be a righteous and holy man. When Herod heard John, he was greatly puzzled; yet he liked to listen to him.