And they did all eat, and were filled.

Jamieson-Fausset-Brown Bible Commentary

42. And they did all eat, and were filled-All the four Evangelists mention this: and John (Joh 6:11) adds, "and likewise of the fishes, as much as they would"-to show that vast as was the multitude, and scanty the provisions, the meal to each and all of them was a plentiful one. "When they were filled, He said unto His disciples, Gather up the fragments that remain, that nothing be lost" (Joh 6:12). This was designed to bring out the whole extent of the miracle.

Matthew Henry's Concise Commentary

6:30-44 Let not ministers do any thing or teach any thing, but what they are willing should be told to their Lord. Christ notices the frights of some, and the toils of others of his disciples, and provides rest for those that are tired, and refuge for those that are terrified. The people sought the spiritual food of Christ's word, and then he took care that they should not want bodily food. If Christ and his disciples put up with mean things, surely we may. And this miracle shows that Christ came into the world, not only to restore, but to preserve and nourish spiritual life; in him there is enough for all that come. None are sent empty away from Christ but those who come to him full of themselves. Though Christ had bread enough at command, he teaches us not to waste any of God's bounties, remembering how many are in want. We may, some time, need the fragments that we now throw away.