1 At that particular time Herod, the district ruler, heard the report about Jesus
2 and said to his servants: This is John the Baptist. He was raised up from the dead, and this is why the powerful works are operating in him.
3 For Herod had arrested John and bound him and put him away in prison on account of Herodias the wife of Philip his brother.
4 For John had been saying to him: It is not lawful for you to be having her.
5 However, although he wanted to kill him, he feared the crowd, because they took him for a prophet.
6 But when Herod's birthday was being celebrated the daughter of Herodias danced at it and pleased Herod so much 7 that he promised with an oath to give her whatever she asked.
8 Then she, under her mother's coaching, said: Give me here upon a platter the head of John the Baptist.
9 Grieved though he was, the king out of regard for his oaths and for those reclining with him commanded it to be given; 10 and he sent and had John beheaded in the prison.
11 And his head was brought on a platter and given to the maiden, and she brought it to her mother.
12 Finally his disciples came up and removed the corpse and buried him and came and reported to Jesus (Matthew 14).

14 Now it got to the ears of King Herod, for the name of [Jesus] became public, and people were saying: John the baptizer has been raised from the dead, and on that account the powerful works are operating in him.
15 But others were saying: It is Elijah. Still others were saying: It is a prophet like one of the prophets.
16 But when Herod heard it he began to say: The John that I beheaded, this one has been raised up.
17 For Herod himself had sent out and arrested John and bound him in prison on account of Herodias the wife of Philip his brother, because he had married her.
18 For John had repeatedly said to Herod: It is not lawful for you to be having the wife of your brother.
19 But Herodias was nursing a grudge against him and was wanting to kill him, but could not.
20 For Herod stood in fear of John, knowing him to be a righteous and holy man; and he was keeping him safe. And after hearing him he was at a great loss what to do, yet he continued to hear him gladly.
21 But a convenient day came along when Herod spread an evening meal on his birthday for his top-ranking men and the military commanders and the foremost ones of Galilee.
22 And the daughter of this very Herodias came in and danced and pleased Herod and those reclining with him. The king said to the maiden: Ask me for whatever you want, and I will give it to you.
23 Yes, he swore to her: Whatever you ask me for, I will give it to you, up to half my kingdom.
24 And she went out and said to her mother: What should I ask for? She said: The head of John the baptizer.
25 Immediately she went in with haste to the king and made her request, saying: I want you to give me right away on a platter the head of John the Baptist.
26 Although he became deeply grieved, yet the king did not want to disregard her, in view of the oaths and those reclining at the table.
27 So the king immediately dispatched a body guardsman and commanded him to bring his head. And he went off and beheaded him in the prison 28 and brought his head on a platter, and he gave it to the maiden, and the maiden gave it to her mother.
29 When his disciples heard of it they came and took up his corpse and laid it in a memorial tomb (Mark 6).

Herod knew John to be a righteous and holy man, i.e. sealed and sanctified.