Adam Clarke on John 13:4

He riseth from supper - Not from eating, as Bishop Pearce has well observed, but from his place at table; probably the dishes were not as yet laid down, though the guests were seated. According to the custom of the Jews and other Asiatics, this washing must have taken place before the supper. See on Joh 13:2 (note).

Laid aside his garments - That is, his gown or upper coat, with the girdle wherewith it was girded close to his tunic or under coat; and, instead of this girdle, he tied a towel about him:

1. that he might appear in the character of a servant; and

2. that he might have it in readiness to dry their feet after he had washed them.