Albert Barnes on John 21:13

Jesus then cometh, and taketh bread, &c. It is not said that Jesus himself ate with them, but he gave them food. The design of this interview seems to have been to convince them that he had truly risen from the dead. Hence he performed a miracle before they suspected that it was he, that there might be no room to say that they had ascribed to him the power of the miracle through friendship and collusion with him. The miracle was such as to satisfy them of its truth, and was, in accordance with all his works, not for mere display, but for utility. He remained with them, was with them at their meal, conversed with them, and thus convinced them that he was the same Friend who had died.

(f) "Jesus then cometh" Acts 10:41