John 2:6

There were set, &c. Christ then made use of these water-pots that it might be the more clearly evident that they had no wine in them; and so the turning the water into wine in such vessels might be the more conspicuous.

Purification : by which the Jews according to their traditions were accustomed at their feasts to wash their hands, if they happened to touch anything unclean at the table. (See S. Mark 7:3.)

Tropologically, S. Bernard expounds thus (Serm. 1 in Domin. 1, post. Oct. Epiph.): The six waterpots are the six purifying virtues of the soul. "The first waterpot, and the first cleansing, is in compunction, of which we read, that in the very hour in which the sinner shall groan, I will no more remember all their iniquities. The second is confession; for all things are washed by confession. The third is the giving of alms; for we read in the Gospel, 'Give alms, and behold all things are clean unto you.' The fourth, forgiveness of injuries; for we say when we pray, 'Forgive us our debts, as we forgive those who are indebted to us.' The fifth is affliction of the body; for we pray that we, being purified by abstinence, may sing glory to God. The sixth is obedience to the commandments: even as the disciples heard what may we too deserve to hear, 'Ye are clean through the word which I have spoken unto you.'" He then applies the rest as follows: "They are filled with water, that they may be kept in the fear of God, since the fear of the Lord is the fountain of life." Then he adds: "But by the Divine power the water is changed into wine when perfect love casts out fear. Now the waterpots are said to be of stone, not because of hardness, but for steadfastness; for they contained two or three firkins apiece."

Two or three firkins Greek, measures. This measure was the same as the Hebrew ephah or bath.