Save James the Lord’s brother - That the James here referred to was an apostle is clear. The whole construction of the sentence demands this supposition. In the list of the apostles in Matthew 10:2-3, two of this name are mentioned, James the son of Zebedee and brother of John, and James the son of Alpheus. From the Acts of the Apostles, it is clear that there were two of this name in Jerusalem. Of these, James the brother of John was slain by Herod Acts 12:2, and the other continued to reside in Jerusalem, Acts 15:13; Acts 21:13. This latter James was called James the Less Mark 15:40, to distinguish him from the other James, probably because he was the younger. It is probable that this was the James referred to here, as it is evident from the Acts of the Apostles that he was a prominent man among the apostles in Jerusalem. Commentators have not been agreed as to what is meant by his being the brother of the Lord Jesus. Doddridge understands it as meaning that he was “the near kinsman” or cousin-german to Jesus, for he was, says he, the son of Alpheus and Mary, the sister of the virgin; and if there were only two of this name, this opinion is undoubtedly correct.
In the Apostolical Constitutions (see Rosenmuller) three of this name are mentioned as apostles or eminent men in Jerusalem; and hence, many have supposed that one of them was the son of Mary the mother of the Lord Jesus. It is said Matthew 13:55 that the brothers of Jesus were James and Joses, and Simon, and Judas; and it is remarkable that three of the apostles bear the same names; James the son of Alpheus, Simon Zelotes, and Judas, John 14:22. It is indeed possible, as Bloomfield remarks, that three brothers of our Lord and three of his apostles might bear the same names, and yet be different persons; but such a coincidence would be very remarkable, and not easily explained. But if it were not so, then the James here was the son of Alpheus, and consequently a cousin of the Lord Jesus. The word “brother” may, according to Scriptural usage, be understood as denoting a near kinsman. See Schleusher (Lexicon 2) on the word ἀδελφός adelphos. After all, however, it is not quite certain who is intended. Some have supposed that neither of the apostles of the name of James is intended, but another James who was the son of Mary the mother of Jesus. See Koppe in loc. But it is clear, I think, that one of the apostles is intended. Why James is particularly mentioned here is unknown. Since, however, he was a prominent man in Jerusalem, Paul would naturally seek his acquaintance. It is possible that the other apostles were absent from Jerusalem during the fifteen days when he was there.