Theophylact of Ohrid — as excerpted in the Catena Aurea on Mark 6:35-44

“He also looks up to heaven, that He may teach us to seek our food from God, and not from the devil, as they do who unjustly feed on other men’s labours. By this also He intimated to the crowd, that He could not be opposed to God, since He called upon God. And He gives the bread to His disciples to set before the multitude, that by handling the bread, they might see that it was an undoubted miracle. It goes on: And they did all eat, and were filled: and they took up twelve baskets full of the fragments. Twelve baskets of fragments remained over and above, that each of the Apostles, carrying a basket on his shoulder, might recognise the unspeakable wonder of the miracle. For it was a proof of overflowing power not only to feed so many men, but also to leave such a superabundance of fragments. Even though Moses gave manna, yet what was given to each was measured by his necessity, and what was over and above was overrun with worms. Elias also fed the woman, but gave her just what was enough for her; but Jesus, being the Lord, makes his gifts with superabundant profusion.”