John Chrysostom

Since however they still spake of the multitude merely, and the place, and the wilderness (for "whence," it is said, "should we have in a wilderness so many loaves, as to fill so great a multitude"?); and not even so understood what He said, He proceeds to contribute His own part, and saith unto them, "How many loaves have ye? And they say, Seven, and a few little fishes." And they no more say, "But what are these among so many?" as they had said before. …

Homily on the Gospel of Matthew 53 ↗

Theophylact of Ohrid

He teaches frugality by having them sit on the ground; and He teaches us to give thanks before eating by Himself giving thanks. Do you ask why it is that when there were five loaves and five thousand being fed, twelve baskets remained, but here where there are more loaves and fewer people only seven baskets were left over? It could be said either that spyrides were a larger type of basket than kophinoi, or that He did not wish the numerical equality of this miracle with the previous one to cause it to be forgotten. …

Commentary on Matthew ↗

Augustine of Hippo

Surely it will not be out of place to suggest upon this miracle, that if any of the Evangelists who had not given the miracle of the five loaves had related this of the seven loaves, he would have been supposed to have contradicted the rest. But because those who have related the one, have also related the other, no one is puzzled, but it is understood at once that they were two separate miracles. …

Catena Aurea by Aquinas ↗

Thomas Aquinas

Then how much material was at hand is set forth; hence Jesus said to them: how many loaves have you? And he did not ask as one who did not know, but so that the miracle might be shown. Hence he also had them recall the few fishes, above, in the other miracle. And it is said that they had five loaves and two fishes, in which the teaching of the law was signified; and those loaves were of barley; here there are seven, and they are not said to be of barley, in which is signified the new law formed by the sevenfold grace of God. …

Commentary on Matthew ↗

Glossa Ordinaria

The seven loaves are the Scripture of the New Testament, in which the grace of the Holy Spirit is revealed and given. And these are not as those former loaves, barley, because it is not with these, as in the Law, where the nutritious substance is wrapped in types, as in a very adhesive husk; here are not two fishes, as under the Law two only were anointed, the King, and the Priest, but a few, that is, the saints of the New Testament, who, snatched from the waves of the world, sustain this tossing sea, and by their example …

Catena Aurea by Aquinas ↗