You also allow them to claim infallibility, a title which no man deserves except Jesus Christ.
First of all, did you determine thet the Catholic doctrines were unbiblical????if so, how??
Infallibility is, indeed scriptural for the Catholic church...what you shall bind on Earth will be bound in Heaven, what you loose on Earth shall be loosed in Heaven......do you think that Christ would have designated this power, and then allowed men to act in error????...I think not...he protects His church from error in matters of faith and morals.....
I think the more correct term would be extra-biblical.
The alleged first pope has written:
2 Peter 1:3
His divine power has given us everything we need for a godly life through our knowledge of him who called us by his own glory...
do you think that Christ would have designated this power, and then allowed men to act in error????...
Joh 2:23 Because of the miraculous signs Jesus did in Jerusalem at the Passover celebration, many began to trust in Him.
Joh 2:24 But Jesus didn’t trust them, because He knew human nature.
Joh 2:25 No one needed to tell Him what mankind is really like.
You have also confused the visible and invisible church as described by your St Augustine.