Mark 6:17-20 says, 17 "For it was Herod who had sent and seized John and a bound him in prison for the sake of Herodias, his brother Philip's wife, because he had married her. 18 For John had been saying to Herod, 'It is not lawful for you to have your brother's wife.' 19 And Herodias had a grudge against him and wanted to put him to death. But she could not, 20 for Herod feared John, knowing that he was a righteous and holy man, and he kept him safe. When he heard him, he was greatly perplexed, and yet he heard him gladly."
Mark 6:14 - 29
ESV - 14 King Herod heard of it, for Jesus' name had become known. Some said, "John the Baptist has been raised from the dead. That is why these miraculous powers are at work in him. 15 But others said, "He is Elijah." And others said, "He is a prophet, like one of the prophets of old.
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