Fill the water-pots with water. The servants might be apt to look upon this injunction as absurd; for they had already more than enough of water. But in this way the Lord often acts towards us, that his power may be more illustriously displayed by an unexpected result; though this circumstance is added to magnify the miracle; for when the servants drew wine out of vessels which had been filled with water, no suspicion can remain.

With water - This was done by the servants employed at the feast. It was done by "them," so that there might be no opportunity of saying that the disciples of Jesus had filled them with wine to produce the "appearance" of a miracle. In this case there could be no deception. The quantity was very considerable. The servants would know whether the "wine" or "water" had been put in these vessels. It could not be believed that they had either the power or the disposition to impose on others in this manner, and the way was therefore clear for the proof that Jesus had really changed what was known to be water into wine.
To the brim - To the top. So full that no wine could be poured in to give the appearance of a mixture. Further, vessels were used for this miracle in which wine had not been kept. These pots were never used to put wine in, but simply to keep "water" in for the various purposes of ablution. A large number was used on this occasion, because there were many guests.

Jesus saith unto them,.... To the servants that waited at the feast,
fill the water pots with water. The Ethiopic version adds, "to their brims", as they did. Christ chose the water pots, and not the vessel, or vessels, or bottles, now empty, out of which they had drank their wine; that it might not be said that there was any left therein, which gave colour and flavour to the water: and he ordered them to be filled with water by the servants, that they might take notice, and be witnesses, that that, and nothing else, was put into them; and up to the brims, so that they could not he capable of having any other liquor infused into them:
and they filled them up to the brim; strictly observing the orders of Christ, and the instructions of his mother.

Fill . . . draw . . . bear--directing all, but Himself touching nothing, to prevent all appearance of collusion.