John Chrysostom

As our Lord was not with them regularly, and the Spirit was not given them, and they had received no commission, and had nothing to do, they followed the trade of fishermen: And on this wise showed He Himself. There were together Simon Peter, and Thomas called Didymus, and Nathanael of Cana in Galilee; he who was called by Philip, and the sons of Zebedee, i. e. James and John, and two other of His disciples. Simon Peter saith unto them, I go a fishing. (Hom. …

Catena Aurea by Aquinas ↗

Gregory the Dialogist

It should also be noted that the Lord is described as having his last banquet with seven disciples; for Peter and Thomas, Nathanael, the sons of Zebedee, and two others of his disciples are mentioned as having been present. Why does he celebrate the last banquet with seven disciples, unless because he announces that only those who are full of the sevenfold grace of the Holy Spirit will be with him in eternal refreshment? All this present time also unfolds in seven days, and often perfection is designated by the number seven. …

Forty Gospel Homilies, Homily 24 ↗

Thomas Aquinas

In describing this appearance, he first mentions the persons to whom Christ appeared; what they were doing; and thirdly, the circumstances of this appearance. Christ appeared to seven persons. The Evangelist says that there were together Simon Peter, who had denied him, Thomas called the Twin, who was not present at the first appearance, Nathanael of Cana in Galilee, who is thought to be the brother of Philip, the sons of Zebedee, that is, James and John, and two others of his disciples not explicitly named. …

Commentary on John ↗

Bonaventure

There were together Simon Peter and Thomas, who is called Didymus, and Nathanael, who was from Cana of Galilee, and the sons of Zebedee and two others of his disciples. And thus there were seven, because such a number is fitting and sufficient for every kind of testimony. …

Commentary on John, Chapter 21 ↗