I had the idea once of Islam conquering more Christian lands in its early stages, when the doctrines were still being defined.
You might end up with Islam essentially becoming Christianity--God unleashed the Arabs on the formerly Roman Christian lands to punish them for spending money on overly-elaborate churches instead of on the poor, loaning at interest, persecuting other Christians, etc.
Mohammed and Abu Bakr could be remembered as divinely anointed bearers of wrath in the mold of Joshua (the Canaanites) and Jehu (the Israelite royal family).
First, he meant while Islamic doctrine was still forming. Not necesarily useful here, but that's what he meant.
Also, there were still plenty of powerful heresies that challenged the "established doctrine" of Nicene Creed Christianity at the time(Monophysites, Nestorians, Arians, etc.), not to mention the differences within the supposedly united Christian church though.at the time of Islam's rise. It might be possible that if Islam conquers areas that are more heretical than orthodox, there could be some heavy influence between the two religions. I don't picture a Chrislamic religion coming to being
Early Islam was not
that fluid. The basic theology had been already set up, including the default view on Jesus. Remember also in its early days Islam was quite highly politically vigorous, as technically it was(and still is) also a political religion,
officially. And the dhimmi system had maybe actually helped the muslims to ensure themselves how they were different from the Christians. It seems that, as long as muslims won't get away from the reach of any Islamic religious center, their brand of Islam won't fuse with anybody.
Also, it seems that what caused early Islam to be not so indifferenciable from Christianity was less the factor from Islam's side, rather from the factor of Christianity being so diverse at that time. It was almost like, sect that has a positive opinion about Jesus is Christianity. Interactions and religious discussions between Christians and Muslims might had led to that situation. Besides, I would think that the muslims would've had wanted their Christian subject to be at ease under their rule....
As said above, military domination is overrated (as very frequently in this forum I dare say). Conquests rather tend to prevent mutual influence of religions beyond a certain limit (either the conqueror decrees the religion, or doesn't interfere).
I can see only two major possibilities of a potential "merge":
- Out of a modern-time desire to emphasize common ideas and to overcome misunderstandings and conflicts. ( I presume that both the mentioned Nigerian movement and this very thread originate from a similar universe of ideas.)
- In the early days of Islam, Muhammad's lore finds significant followers among Christian peoples - who integrate it somehow. This might produce something halfway between Christinanity and Islam - but it would not wipe away all of Christianity.
Agrees with this point mostly. About the second possibility though, I'm not sure about that. First, parts of Arabia were Christian just prior to Islamic era, like Yemen, and didn't the Bahrain area used to be the center of Nestorianism (they like, converted in mass, IIRC) ? Second, like you say this bulk of Christians can't really be gain through conquest. So I'd say either the first way, or getting some significant enough number muslims far away from the gravity of Islamic religious center(s), where there happens to be a Christian community that's as strong enough(usually on rich and fertile soils). Especially if the said Christians are not a majorly trade-based economy...
Sorry, I got that wrong.
However, Islam had much less of a "forming" period than for instance the Old Church, right?
Yes, for the reason I already stated above.