And the disciples of John and of the Pharisees used to fast:
and they come and say unto him, Why do the disciples of John and of the
Pharisees fast, but thy disciples fast not? And Jesus
said unto them, Can the children of the bridechamber fast, while the
bridegroom is with them? as long as they have the bridegroom with them,
they cannot fast. But the days will come, when the bridegroom shall be taken away from them, and then shall they fast in those days.
No man also seweth a piece of new cloth on an old garment: else the new
piece that filled it up taketh away from the old, and the rent is made
worse. And no man putteth new wine into old bottles: else
the new wine doth burst the bottles, and the wine is spilled, and the
bottles will be marred: but new wine must be put into new bottles.
In Chrysostom's Homily 30 on Matthew, he says:
"This is the disease, which Christ long before was eradicating, in the words, 'When you fast, anoint your head, and wash your face;' (Matt.6:17) foreknowing the evils that spring therefrom. But yet He does not rebuke even these, nor say, 'O you vainglorious and over-busy;' but he discourses to them with all gentleness, saying, 'The children of the bride-chamber cannot fast, as long as the bridegroom is with them.' Thus, when others were to be spoken for, the publicans I mean, to soothe their wounded soul, He was more severe in His reproof of their revilers; but when they were deriding Himself and His disciples, He makes his reply with all gentleness."
"Now their meaning is like this; 'Granted,' say they, 'You do this as a physician; why do Your disciples also leave fasting, and cleave to such tables?' Then to make the accusation heavier, they put themselves first, and then the Pharisees; wishing by the comparison to aggravate the charge. For indeed 'both we,' it is said, 'and the Pharisees, fast oft.' And in truth they did fast, the one having learned it from John, the other from the law; even as also the Pharisee said, 'I fast twice in the week.' (Luke 18:12)"What then says Jesus?…He called Himself a physician, but here a bridegroom; by these names revealing His unspeakable mysteries…recalling to their mind John's words, when he said, 'He that has the bride, is the bridegroom, but the friend of the bridegroom, which stands and hears Him, rejoices greatly because of the bridegroom's voice.' (Jn.3:29)"…the present time is of joy and gladness, therefore do not bring in the things which are melancholy…fasting is a melancholy thing, not in its own nature, but to them that are yet in rather a feeble tate; for to those at least that are willing to practise self-command, the observance is exceedingly pleasant and desirable….when the body is in health, the spirits are high, so when the soul is well conditioned, the pleasure is greater…what they did was not of gluttony, but pertained to some marvellous dispensation…"
"Then what He had done before, this He does here again. I mean, that as He, when they were attempting to prove Him blameable for eating with sinners, proved to them on the contrary, that His proceeding was not only no blame, but an absolute praise to Him: so here too, when they wanted to show of Him, that He knows not how to manage His disciples, He signifies that such language was the part of men not knowing how to manage their inferences, but finding fault at random…"