At that time: Herod sent and apprehended John, and bound him in prison for the sake of Herodias, the wife of Philip his brother, because he had married her. For John said to Herod: It is not lawful for thee to have thy brother’s wife. Now Herodias laid snares for him, and was desirous to put him to death, and could not. For Herod feared John, knowing him to be a just and holy man, and kept him, and when he heard him, did many things; and he heard him willingly. And when a convenient day was come, Herod made a supper for his birthday, for the princes, and tribunes, and chief men of Galilee. And when the daughter of the same Herodias had come in, and had danced, and pleased Herod and them that were at table with him, the king said to the damsel: Ask of me what thou wilt, and I will give it thee. And he swore to her: Whatsoever thou shalt ask, I will give thee; though it be the half of my kingdom. Who, when she was gone out, said to her mother, What shall I ask? But she said: The head of John the Baptist. And when she was come in immediately with haste to the king, she asked, saying: I will that forthwith thou give me in a dish the head of John the Baptist. And the king was struck sad; yet because of his oath, and because of them that were with him at table, he would not displease her; but sending an executioner he commanded that his head should be brought in a dish. And he beheaded him in the prison, and brought his head in a dish, and gave it to the damsel, and the damsel gave it to her mother. Which his disciples hearing, came, and took his body, and laid it in a tomb. (Mark vi. 17-29)
Below is an excerpt from the weekly general audience of Pope Benedict XVI delivered on 29th August, 2012, Feast of the Beheading of St. John the Baptist:
“As a last act, the Baptist bears witness with his blood to his fidelity to God’s commandments, without giving up or turning back, thus fulfilling his mission to the end. St. Bede, a 9th century monk, in his Homilies says: St. John, for Christ, gave up his life, even though [his persecutor] had not demanded that he should deny Jesus Christ, but only that he should keep silent about the truth. And he did not keep silent about the truth, and thus he died for Christ who is the Truth. For love of the truth, he did not give in to compromises with those who were powerful, nor was he afraid to address strong words to the one who lost his way to God.
“Now we see this great figure — this force — in his passion, in his resistance against the powerful. We ask: where does this life come from, this interiority, which is so strong, so principled, so consistent, which is spent so totally for God and in preparing the way for Jesus? The answer is simple: from his relationship with God, from prayer, which is the guiding thread of his entire life. […]
“Dear brothers and sisters, celebrating the martyrdom of St. John the Baptist also reminds us — Christians in our own times — that we cannot give into compromise when it comes to our love for Christ, for his Word, for his Truth. The Truth is the Truth; there is no compromise. The Christian life requires, as it were, the “martyrdom” of daily fidelity to the Gospel; the courage, that is, to allow Christ to increase in us and to direct our thoughts and actions. But this can only occur in our lives if our relationship with God is strong.”