Ben,
I've had so much on my plate (on top of my limited internet time) that it's taking me awhile to address your citations of Bauckham. Now I see that I was going by incomplete information. I gathered from the link I gave upthread that Bauckham only had an issue with the interpretation of Hegesippus' "holy place" to mean the Holies of Holies (by Jerome, Epiphanius and whoever else) because I didn't see anything that indicated that he had one with the interpretation of it as the priestly area of the Temple, but this citation you gave from his chapter in
James the Just and Christian Origins (which I had not been able to see previously in its entirety on Google books) puts that idea to rest:
From any knowledge of what occurred in the Temple or even of what the Torah prescribed, it would be incomprehensible that James alone could be admitted to the Temple building, the holy place, which all priests could enter.
Regarding the word Hegesippus uses ("holy place"), it appears to also be used in Hebrews 9:2 and doesn't mean the Holy of Holies:
A tabernacle was set up. In its first room were the lampstand and the table with its consecrated bread; this was called the Holy Place.
A comment about this on the biblehub says:
Sanctuary.—Or, holy place. The same word is applied to the Holy of Holies in Hebrews 8:2; Hebrews 9:8; Hebrews 12:24-25; Hebrews 10:19; and probably in Hebrews 13:11. This verse and the next give the proper names of the two parts of the Tabernacle, which must be used when the one is to be distinguished from the other. Where there is no risk of mistake the simpler designation is sufficient. (See Leviticus 16:2; Leviticus 16:17; Leviticus 16:20.) It will be observed that here and in Hebrews 9:3; Hebrews 9:6-7, these divisions are spoken of as if two distinct Tabernacles.
http://biblehub.com/commentaries/hebrews/9-2.htm
So I'm at least comfortable with the idea (which Bauckham endorses but still thinks is improbable then) that Hegesippus means that James entered the "holy place" where the priests served and not the Holy of Holies. And maybe this is "wacky" too (if somewhat less so), but I'm trying (unsuccessfully so far) to get out of the realm of opinion and find some corroborating evidence that Nazirites were forbidden to enter the "holy place" (meaning not the Holy of Holies). Given all the talk about the similarities between Nazirites and priests, it seems like this might be a grey area (but if not then that's fine). I feel like I'm overlooking something obvious, but so far nothing is jumping out at me, and all I have for support then is Lange (who seems to imply that there is no law against it) and to a lesser extent Chilton (who mentions Nazirites being able to go at least "in the vicinity" of the holy place):
This expression is falsely interpreted as designating the holiest of holies. The expression may admit of such an interpretation, but the Jewish law forbids it. The acknowledged Nazarite might probably go with the priests into the temple proper ...
https://books.google.com/books?id=zdI3A ... us&f=false
... although Hegesippus' assertion that James could actually enter the sanctuary of the temple seems exaggerated, his acceptance of a Nazirite regime, such as Acts 21 explicitly associates him with, would account for such a remembrance of him, in that Nazirites were to be presented in the vicinity of the sanctuary where the sacrifice was offered.
https://books.google.com/books?id=T8LQq ... us&f=false
Regarding Bauckham's opinion that Hegesippus based his account of James on various OT passages (like Ezek. 44), I'm finding that difficult to accept, since Hegesippus specifically mentions the OT when he says something about James that pertains to it regarding his nickname and his death:
Because of his exceeding great justice he was called the Just, and Oblias, which signifies in Greek, 'Bulwark of the people' and 'Justice,' in accordance with what the prophets declare concerning him.
And they cried out, saying, 'Oh! Oh! The just man is also in error.' And they fulfilled the Scripture written in Isaiah, 'Let us take away the just man, because he is troublesome to us: therefore they shall eat the fruit of their doings.'
So why would he not similarly say, "He alone was permitted to enter into the holy place; for he wore not woolen but linen garments, in accordance with what the prophets declare concerning him"?
I look at the parallels this way. Did Hegesippus make up that James did not eat meat or anoint himself with oil because of Dan. 10:3, or did James not eat meat or anoint himself with oil because that is what ascetics like Daniel did? I'm inclined to think it's the latter.
Dan. 10:3:
I ate no delicacies, no meat or wine entered my mouth, nor did I anoint myself at all, for the full three weeks.
EH 2.23.5:
... he drank no wine nor strong drink, nor did he eat flesh ... he did not anoint himself with oil ...
The other parallels Bauckham mentions also seem vague to me. Take John 12:42, for example.
Yet at the same time many even among the leaders believed in him. But because of the Pharisees they would not openly acknowledge their faith for fear they would be put out of the synagogue ...
EH 2.23.10:
Therefore when many even of the rulers believed, there was a commotion among the Jews and Scribes and Pharisees, who said that there was danger that the whole people would be looking for Jesus as the Christ.
I look at this two ways. First, Eusebius does not say that Hegesippus knew John; and second, if the above was the case in Jesus' time, why couldn't it have been the case in James' time too? And if there is a literary connection between them, how do we know that John wasn't dependent on Hegesippus (as I suspect was the case for Luke/Acts)?
And Luke 20:21-22
So the spies questioned him: “Teacher, we know that you speak and teach what is right, and that you do not show partiality but teach the way of God in accordance with the truth. Is it right for us to pay taxes to Caesar or not?”
EH 2.23.11-12:
Therefore, persuade the multitude not to be led astray concerning Jesus. For the whole people, and all of us also, have confidence in you. Stand therefore upon the pinnacle of the temple, that from that high position you may be clearly seen, and that your words may be readily heard by all the people. For all the tribes, with the Gentiles also, have come together on account of the Passover.'
The aforesaid Scribes and Pharisees therefore placed James upon the pinnacle of the temple, and cried out to him and said: 'You just one, in whom we ought all to have confidence, forasmuch as the people are led astray after Jesus, the crucified one, declare to us, what is the gate of Jesus.'
Again, Hegesippus is not said to have known Luke. If there was any borrowing I reckon it would have come from Matthew/the Gospel of the Hebrews.
Mt. 22:16-17:
They [the Pharisees] sent their disciples to Him along with the Herodians. “Teacher, they said, “we know that You are honest and that You teach the way of God in accordance with the truth. You defer to no one, because You pay no attention to external appearance. So tell us what You think. Is it lawful to pay taxes to Caesar, or not?”
But even still the connection seems vague to me. It seems similar to suggesting that Hegesippus' reference to James being stoned and beaten with a club is based on 2 Cor. 11:25:
Three times I was beaten with rods, once I was pelted with stones.
To me James' death and Paul's punishment seem more in keeping with the climate of the times (e.g., Pes. 57a above) rather than Hegesippus being dependent on Paul (who he is also not said to have known in any event).
Mt. 4:5-6 seems to have a little more merit (especially since Hegesippus knew Matthew/the Gospel of the Hebrews).
Then the devil took Him to the holy city and set Him on the pinnacle of the temple. “If You are the Son of God,” he said, “throw Yourself down.
I think the difference is that James is said to have been placed on the pinnacle of the Temple so that "from that high position you may be clearly seen, and that your words may be readily heard by all the people. For all the tribes, with the Gentiles also, have come together on account of the Passover." That he was afterwards pushed off was only because of what James said and was not the reason they had placed him on the pinnacle.
And when many were fully convinced and gloried in the testimony of James, and said, 'Hosanna to the Son of David,' these same Scribes and Pharisees said again to one another, 'We have done badly in supplying such testimony to Jesus. But let us go up and throw him down, in order that they may be afraid to believe him.'
So alright, maybe, maybe, but I'm not yet convinced.