That is right. Copies and a merges with older traditions.
And just to address the opposite. There were many prophets, major and minor after Jesus, so giving him the cult and prominence the Christians give him is totally undeserved.
Now for another thought of mine, inspired what we know about medicine nowadays.
For the purpose of this discussion, let us accept that Jesus was a real person and was indeed crucified.
What if he did not die but has fallen in temporary comma? There are cases of people who are in comma for years on end, neither dead or alive. They are kept in suspended animation, sometimes even put into this state for medical purposes.
Suppose our Savior was in similar medical state for 3 days, there is enough water and nutrients in human body to defer death for a while. Much longer commas can be sustained, just with a drip containing water with bit of salt and sugar. For longer periods you just add some vitamins and minerals.
The guards watching over the crucified prisoners would be only too happy to declare him dead after few pokes with spear or sword, patient in comma do not respond to such stimulation. Evangelists do not tell us that medical practitioner was called to issue a death certificate, so in the absence of proof, it is safe to assume that there was no doctor or even quack on the scene. Remember, in those days Jesus was not that famous, officially he was just a trouble maker, riding on an ass, organizing the odd rally with few magic tricks and stirring speeches and messing with legitimate licensed business of the money changers at the temple.
Body was released to the family for burial and again no medical training there. Mary was a housewife and the disciples were tradesmen or farmers, Jesus was a carpenter,Petr was a fisherman etc. Not a medical doctor between them.
So they washed him, dressed him in clean robe and placed him in the tomb, with some chanting, I suppose. Then he came about after three days, pushed away a rock and walked out to surprise few passers by. Than he hid himself only speaking to his mum and his girlfriend and few really close mates.
He probably said that he does not want to be crucified again, because it is quite painful and he has done enough for the cause, time for somebody else to lead the mission.
Everybody thought it was a bloody miracle, because they have not been to medical school either and were not familiar with temporary commas and suspended animations.
So the disciples went around to tell in secret to the true believers what they saw, while Jesus went back to his father's business and made money making roof trusses and timber frames for the local dwellings and lived quiet life in Nazareth unaware what was about to unfold in future centuries in his name.
I would say this is a plausible explanation to a the miracle of resurrection, wouldn't you?
