I thought simply reading the chapter with the line in [Acts 12.2] and again with the line out might provide reason enough to consider that Acts 12.2 is an interpolation. However, the following provides in detail some possibilities:
"From Paul's letters it shows that he met with Peter and James at some early point, and then he went back to Jerusalem 14 years later and met with the apostles again. Nowhere in Paul's letters does Paul indicate that the James he met the first time is different from the James that he met the second time, and at any rate, he mentions that the apostle James was "the Lord's brother" when discussing the first meeting. Paul also never says anything about James dying. Acts says that Paul first met the disciples in Damascus, which contradicts what the letters of Paul say. It's certain that Acts is not totally accurate, and that the author of Acts made a few things up or based some story elements on traditions that were made up. The book of Acts is where the Gospel story was merged with the apostolistic reality, and as can be expected when blending fact with fiction, inconsistencies arose. This is all the more interesting in Acts because there is a clear differentiation between Acts 1-12 and the later chapters, which contain a more historical story line.
We know one thing for sure though, which is that as far as the author of Acts was concerned, "James" was not a literal brother of Jesus, because a brother of Jesus named James is never mentioned by the author of Acts in either of his works. He wouldn't just introduce an unknown character out of the blue that is supposed to be the real life brother of Jesus without even stating that the person was the brother of Jesus. In Christian tradition, and in most Bibles that have footnotes, the mentions of James after the supposed killing of James son of Zebedee are referenced as the brother of Jesus via footnotes that tie this James to the passage from Paul in Galatians that says "the Lord's brother". Clearly, though, this is not legitimate as nothing within Acts itself makes this association. So, what are the possible answers to who this James is?
There are several possibilities. The first possibility is that the James mentioned after the supposed death of James son of Zebedee is James son of Alphaeus who was also listed as an apostle who was among them during this incident. This would mean that Paul possibly met with James son of Zebedee in Galatians 1 and James son of Alphaeus in Galatians 2.
The second possibility is that the author of Acts somehow got his sources confused and he accidentally recorded the killing of the wrong James, or he put this incident at the wrong place in the time line and in fact Peter and James were not put in prison until later. This could be the case, in which case the killing of "James" in other accounts, such as the accounts of Hegesippus and Josephus, which we looked at in Part I, could be describing the same incident that is described in Acts 12, though Acts 12 is out of order.
This is not unlikely actually, because Acts is considered to exist in two distinct parts, chapters 1 through 12 and chapters 13-28, which are thought to be derived from two different sources that were combined together. In fact there could be overlap with these sections, and thus what is described in Acts 21 could actually have occurred at the same time as what is in Acts 9. These could well be two different descriptions, from two different sources, of the same events, in which case both of the meetings of Paul with James as described in Acts would be talking about James son of Zebedee, and the killing of James son of Zebedee in Acts 12 would likely have occurred in the 60s CE.
If that is the case then the other mentions of the the killing of James, possibly by Josephus and Hegesippus, are really talking about the killing of James son of Zebedee, who was called "James the Just" and "the brother of the Lord". James son of Zebedee would perhaps have had those titles because he was some outstanding community leader.
A third option is that Acts 12:2 is a later interpolation, inserted into the text in order to blot James son of Zebedee out of the history.
In both the writings of Paul and in the Gospels conflict between James son of Zebedee and the others is shown. There was some kind of tension between the brothers of Zebedee and the rest of the apostles. It appears, according to the writings of Paul, that James and John Zebedee held to a more Jewish version of the faith and did not embrace the Gentile apostleship.
In the 1st century, however, James son of Zebedee was considered a pillar of the Christian community, but perhaps later Christians sought to exclude him from the tradition and sever ties to his sect.
There is support for Acts 12:2 being an interpolation within the text itself, because there is no discussion of the death of James, and the narrative goes on as if nothing happened. Indeed if you take that one sentence out no one would ever suspect that the James being talked about in later chapters was no longer James son of Zebedee.
[this is what I was alluding to]
If this James really were killed at this point in the Acts narrative, and this narrative were true, then there would have been no reason for the Gospels to have played up the role of James son of Zebedee in the first place. The playing up of his role in the Gospels was presumably done because of this person's later leadership. This was a means of establishing who the leaders were, by tying them into important roles in the narrative. So much effort was put into establishing the trio of Peter, James, and John in the Gospels, while the brothers of Jesus had one line written about them in each Gospel, which only stated that Jesus rejected them, yet we are to then believe that the James mentioned among the Peter, James, and John of later importance refers to a different James than the one referred to in the Gospels and Acts? This clearly makes no sense.
There is even further support for the idea that James the pillar whom Paul met was not a literal brother of Jesus and was perhaps James son of Zebedee.
One of the few other early mentions of James comes from the
Gospel of Thomas, which does not mention any literal brothers of Jesus, nor does it ascribe a brotherly status to James.
12 The disciples said to Jesus, "We know that you are going to leave us. Who will be our leader?" Jesus said to them, "No matter where you are you are to go to James the Just, for whose sake heaven and earth came into being."
- Gospel of Thomas
This seems like an odd thing to have Jesus say if "James the Just" is the brother of Jesus, as this would have been the perfect place to have Jesus say "Turn to my brother James the Just," etc. Not only would it be odd not to call James his brother here, but it's also odd to give the reason,
"for whose sake heaven and earth came into being." This is quite a strange thing to say in any account, ascribing the entire creation of the universe to the grandeur of this one man.
This leads to other questions. In the synoptic Gospels we have James son of Zebedee, along with his brother John, portrayed as one the the three most important disciples and the one perhaps closest to Jesus. In the Gospel of Thomas we have Jesus saying that "James the Just" is the one
"for whose sake heaven and earth came into being."
What, then, do we have in the Gospel of John?" [now this part gets really interesting] read on at
Jesus Myth Part II - Follow-up, Commentary, and Expansion about 4 fifths of the way down the page.