Mystically, dinner is the first meal, taken early in the spiritual day, and adapted to those who have just entered upon this day. Supper is the last meal, and is set before those who are farther advanced. According to another sense, dinner is the understanding of the Old Testament, the supper the understanding the mysteries hid in the New. Yet even they who sup with Jesus, who partake of the final meal, need a certain washing, not indeed of the top parts of their body, i. e. the soul, but its lower parts and extremities, which cleave necessarily to earth. (c. 4.). It is, And began to wash; for He did not finish His washing till afterwards. The feet of the Apostles were defiled now: All of ye shall be offended because of Me this night. (Matt. 26:31) But afterwards He cleansed them, so that they needed no more cleansing.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: t. xxxii. 2.