I don't give one iota of shit about this issue, personally, but you gotta understand that this statement is treating opinion as fact.
There are great debates about religion and what constitutes Christianity. It most likely should be up to the individual sects to decide what applies, rather than ...you.
Not really. We have 13 letters from Paul that discerned church matters. 9 were sent directly to churches and 4 were sent to his replacements (Timothy and Titus) towards the end of his life. Many of those churches were doing the same things they are doing today during the first century. Many who called themselves Apostles taught contrary to the Disciples. Paul called them out and corrected them just like he did Peter when he had bowed to pressure. Paul corrected the church by emphasizing that Christ ... not human leaders, pedigree, or personal wisdom .... is the absolute center. He corrected their disunity by defining the church as the unified body of Christ, where every member is valuable, but strongly condemned the idea that Christ's redeeming work required any human works or adherence to the Law. The Apostles Peter and John, as well as Jesus' brothers James and Jude also wrote some letters that we have copies of. None contradict each other.
Now we do have different denominations because people can't agree on how to baptize, how to celebrate the Lord's Supper, predestination, and other silly things but nothing that contradicts what is clearly taught as doctrine.
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