Luke 22:10

a man...bearing a pitcher of water A very unusual sight in the East, where the water is drawn by women. He must probably have been the slave of one who was an open or secret disciple; unless we have here a reference to the Jewish custom of the master of a house himself drawing the water with which the unleavened bread was kneaded on Nisan 13. If so the "man bearing a pitcher of water" may have even been the Evangelist St Mark, in the house of whose mother, and probably in the very upper room where the Last Supper was held, the disciples used at first to meet (Acts 12:12). The mysteriousness of the sign was perhaps intended to baffle, as long as was needful, the machinations of Judas.