Neither do men put new wine into old wineskins: else the wineskins break, and the wine runs out, and the wineskins perish: but they put new wine into new wineskins, and both are preserved.
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What he is saying is this: Until a person has been reborn and, having put aside the old person, puts on the new person because of my passion, he cannot observe right fasting and the precepts of temperance. Otherwise, through undue austerity one may lose even the faith one seems to possess. Christ gave two examples: the garment and the old and new wineskins. The old ones denote the scribes and Pharisees. The patch of shrunk cloth and the new wine signify the gospel precepts, which the Jews cannot observe, else a worse tear is made. .