Having mentioned the Baptist, St. Ambrose enters into a description of the events concerning his death, and speaks against dancing and the festivities of the wicked.
26. And since we must not cursorily pass by the mention of so great a man, let us consider who he was, by whom, on what account, how, and at what time he was slain. A just man, he is put to death by adulterers, and the penalty of a capital crime is turned off by the guilty on to the judge. Again the reward of the dancer is the death of the prophet. Lastly (a matter of honour even to all barbarians), the cruel sentence is given in the midst of banqueting and festivities, and the news of the deadly crime is carried from the banquet to the prison, and then from the prison to the banquet. How many crimes are there in one wicked act!
27. A banquet of death is set out with royal luxury, and when a larger concourse than usual had come together, the daughter of the queen, sent for from within the private apartments, is brought forth to dance in the sight of men. What could she have learned from an adulteress but loss of modesty? Is anything so conducive to lust as with unseemly movements thus to expose in nakedness those parts of the body which either nature has hidden or custom has veiled, to sport with the looks, to turn the neck, to loosen the hair? Fitly was the next step an offense against God. For what modesty can there be where there is dancing and noise and clapping of hands?
28. “Then,” it is said, “the king being pleased, said unto the damsel, that she should ask of the king whatsoever she would. Then he swore that if she asked he would give her even the half of his kingdom.” See how worldly men themselves judge of their worldly power, so as to give even kingdoms for dancing. But the damsel, being taught by her mother, demanded that the head of John should be brought to her on a dish. That which is said that “the king was sorry,” is not repentance on the part of the king, but a confession of guilt, which is, according to the wont of the divine rule, that they who have done evil condemn themselves by their own confession. “But for their sakes which sat with him,” it is said. What is more base than that a murder should be committed in order not to displease those who sat at meat? “And,” it follows, “for his oath's sake.” What a new religion! He had better have forsworn himself. The Lord therefore in the Gospel bids us not to swear at all, that there be no cause for perjury, and no need of offending. And so an innocent man is slain that an oath be not violated. I know which to have in the greatest horror. Perjury is more endurable than are the oaths of tyrants.
29. Who would not think when he saw some one running from the banquet to the prison, that orders had been given to set the prophet free? Who, I say, having heard that it was Herod's birthday, and of the state banquet, and the choice given to the damsel of choosing whatever she wished, would not think that the man was sent to set John free? What has cruelty in common with delicacies? What have death and pleasure in common? The prophet is hurried to suffer at a festal time by a festal order, by which he would even wish to be set free; he is slain by the sword, and his head is brought on a platter. This dish was well suited to their cruelty, in order that their insatiate savageness might be feasted.
30. Look, most savage king, at the sights worthy of your feast. Stretch forth your right hand, that nothing be wanting to your cruelty, that streams of holy blood may pour down between your fingers. And since the hunger for such unheard-of cruelty could not be satisfied by banquets, nor the thirst by goblets, drink the blood pouring from the still flowing veins of the cut-off head. Behold those eyes, even in death, the witnesses of your crime, turning away from the sight of the delicacies. The eyes are closing, not so much owing to death, as to horror of luxury. That bloodless golden mouth, whose sentence you could not endure, is silent, and yet you fear. Yet the tongue, which even after death is wont to observe its duty as when living, condemned, though with trembling motion, the incest. This head is borne to Herodias: she rejoices, she exults as though she had escaped from the crime, because she has slain her judge.
31. What say you, holy women? Do you see what you ought to teach, and what also to unteach your daughters? She dances, but she is the daughter of an adulteress. But she who is modest, she who is chaste, let her teach her daughter religion, not dancing. And do you, grave and prudent men, learn to avoid the banquets of hateful men. If such are the banquets, what will be the judgment of the impious?
Source: Concerning Virgins (New Advent)