You're ignoring the apostasy (falling away from the truth) that Paul and Jesus foretold, and the warnings of false teachers:He who rejects the church and the teaching of the church rejects Christ and forfeits any possibility of salvation
2 Thessalonians 2:3 (MKJV):
Let not anyone deceive you by any means. For that Day shall not come unless there first comes a falling away, and the man of sin shall be revealed, the son of perdition,
2 Peter 2 (WEB):1) But false prophets also arose among the people, as false teachers will also be among you, who will secretly bring in destructive heresies, denying even the Master who bought them, bringing on themselves swift destruction.
2) Many will follow their immoral ways, and as a result, the way of the truth will be maligned.
Matthew 24:11 (WEB):2) Many will follow their immoral ways, and as a result, the way of the truth will be maligned.
And many false prophets will rise and deceive many.
We should only believe the teachings of the very early church, as recorded in the Bible - Jude 1:3 (WEB):
Beloved, while I was very eager to write to you about our common salvation, I was constrained to write to you exhorting you to contend earnestly for the faith which was once for all delivered to the saints.