My previous post disappeared into the ether, so apologies if it turns up later and this is a duplicate.
In a simplistic way, I have always tended to compare Paul with Joseph Smith. Both claimed 'vsions and revelations', both started new religions incorporating previous religions, their 'facts' and 'experiences' were uncheckable and unverifiable.
Both new religions, aided by time, distance and space (and obscuration of origins) have become - to one degree or another - 'acceptable, even 'mainstream' to many.
I have always been intrigued by 'Paul' and there are all sorts of theories. Was he the 'wicked deceiver' mentioned in the Dead Sea writings? Who knows. I lived in Cyprus for five years until recently and visited (probably) the spot where he met with Roman governor Sergius Paulinus (that's where he changed his name to Paul) and the curious incident where he blinded the son of Jesus (see Acts). All very strange, but to me it was just a place on my morning walk by the sea to have a beer in the harbour. (may not have been THE 'Jesus' of course).
What does seem to be beyond doubt is that Saul/Paul went off on his travels, spreading his religion. The guys back in Jerusalem, the remnants of the 'Jesus' group, felt compelled to send out their own envoys after him to correct his teachings, brought him back, where he apologised and said he wouldn't do it again.
And - this should never be understated - to understand what was happening, look at the context, what was happening at the time (NT is very sketchy on this).
Always remember, history is written by the victors.