James is without doubt the Bishop of Jerusalem (Acts 12:17, 15:13, 21:18; Galatians 1:19; 2:9-12) and the author of the first Catholic Epistle. His identity with James the Less (Mark 15:40) and the Apostle James, the son of Alpheus (Matthew 10:3; Mark 3:18), although contested by many Protestant critics, may also be considered as certain. There is no reasonable doubt that in Galatians 1:19: "But other of the apostles [besides Cephas] I saw none, saving James the brother of the Lord", St. Paul represents James as a member of the Apostolic college. The purpose for which the statement is made, makes it clear that the "apostles" is to be taken strictly to designate the Twelve, and its truthfulness demands that the clause "saving James" be understood to mean, that in addition to Cephas, St. Paul saw another Apostle, "James the brother of the Lord" (cf. Acts 9:27). Besides, the prominence and authority of James among the Apostles (Acts 15:13; Galatians 2:9; in the latter text he is even named before Cephas) could have belonged only to one of their number. Now there were only two Apostles named James: James the son of Zebedee, and James the son of Alpheus (Matthew 10:3; Mark 3:18; Luke 6:16; Acts 1:13). The former is out of the question, since he was dead at the time of the events to which Acts 15:6 ssq., and Galatians 2:9-12 refer (cf. Acts 12:2). James "the brother of the Lord" is therefore one with James the son of Alpheus, and consequently with James the Less, the identity of these two being generally conceded. Again, on comparing John 19:25 with Matt 27:56, and Mark 15:40 (cf. Mark 15:47; 16:1), we find that Mary of Cleophas, or more correctly Clopas (Klopas), the sister of Mary the Mother of Christ, is the same as Mary the mother of James the Less and of Joseph, or Joses. As married women are not distinguished by the addition of their father's name, Mary of Clopas must be the wife of Clopas, and not his daughter, as has been maintained. Moreover, the names of her sons and the order in which they are given, no doubt the order of seniority, warrant us in identifying these sons with James and Joseph, or Joses, the "brethren" of the Lord. The existence among the early followers of Christ of two sets of brothers having the same names in the order of age, is not likely, and cannot be assumed without proof. Once this identity is conceded, the conclusion cannot well be avoided that Clopas and Alpheus are one person, even if the two names are quite distinct. It is, however, highly probable, and commonly admitted, that Clopas and Alpheus are merely different transcriptions of the same Aramaic word Halphai. James and Joseph the "brethren" of the Lord are thus the sons of Alpheus.
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Hey, no giving away secrets. ;-)
I'm trying to present the material in a Scriptural-based way. People so inclined will just tune out a paragraph from the Catholic Encyclopedia. It's much easier to simply lay out all the "Jameses" in the Bible and ask which one is supposed to be Joseph's son.
SD