Definitely a lot like religion. I really recommend the book "Christianity: the first three thousand years". Post historical crucifixion of Jesus the first few hundred years of Christianity sound like a purity spiral, monarchism, gnosticism, origenism.

The original church in Antioch first applied the word catholic to Christianity (καθολικός / katholikos) but was then later ejected from the western church in 1054 for not being catholic enough.