And He look it, and did eat before them. Christ truly ate of the food, and not in appearance only, after the manner of an angel "I did neither eat nor drink, but ye did see a vision." Tobit xii19. Yet He was not thereby nourished. So Theophylact says, "He ate by some divine power consuming what He was eating." Similarly, S. Augustine: "The thirsty earth, and the burning rays of the sun absorb water, each in a different way; the one because of its need; the other by its power." So D. Thomas and the Schoolmen.
The Vulgate adds, "sumens reliquias, dedit eis;" but these words, although in the Arabic, are absent from the Greek and from the Syriac versions.
Christ eat, not because he stood in need of food to sustain himself after his resurrection, as we sustain our bodies and lives by corporal refreshment; but he did it, to show his disciples that his body was really risen from the dead. (Ven. Bede)