Luke 5:36

Lastly, it is spoken of the fast of the soul, as the context shows, for it follows, But he said, No man putteth a piece of a new garment upon an old. He calleth fasting an old garment, which the Apostle thought should be taken off, saying, Put off the old man with his deeds. (Col. 3:9.) In the same manner we have a series of precepts not to mix up the actions of the old and new man.

(ubi sup.) Or else, The gift of the Holy Spirit being received, there is a kind of fast, which is of joy, which they who are already renewed to a spiritual life most seasonably celebrate. Before they receive this gift, He says they are as old garments, to which a new piece of cloth is most unsuitably sewed on, i. e. any part of the doctrine which relates to the soberness of the new life; for if this takes place, the very doctrine itself also is in a measure divided, for it teaches a general fast not from pleasant food only, but from all delight in temporal pleasures, the part of which that appertains to food He said ought not to be given to men still devoted to their old habits, for therein seems to be a rent, and it agreeth not with the old. He says also, that they are like to old skins, as it follows, And no one putteth wine into old skins.

Inasmuch as wine refreshes us within, but garments cover us without, the garments are the good works which we do abroad, by which we shine before men; wine, the fervour of faith, hope, and charity. Or, The old skins are the Scribes and Pharisees, the new piece and the new wine the precepts of the Gospel.