He riseth from supper - Evidently while they were eating. See John 13:2.
Laid aside his garments - His outer garment. See the notes at Matthew 5:40. This was his mantle or robe, which is said to have been without seam. It was customary to lay this aside when they worked or ran, or in the heat of summer.
Took a towel and girded himself - This was the manner of a servant or slave. See the notes at Luke 17:8.