Are you including the hundreds of variants of Christianity that existed at that time and had wildly different beliefs as well? Or just the ones you agree with?
We know what many of them taught. Not just the ones that I agree with. You're trying to pick on my words again, like you do on all the threads I post on about religion. I made the comment that we know what the early church fathers taught in response to the claim that we only know what later Christianity taught. We know what the Gnostics taught. And we know what the others taught. We have very early writings from them. So comprehensive, in fact, that we can reconstruct almost the entire NT just based on the writings of the early church fathers alone.