Deadly for eternity actually.
Paul said to even check what he taught with scripture but the RCC says check with them before reading scripture.
Kind of right, but not 100%...Christ established a church for that very purpose, otherwise it would not be necessary at all. The very existance of 20,000 "Denomiations" of protestantism prove that fact. Christ established 1 church, Catholicism, and gave her the keys to the kingdom of Heaven, she did just fine for over 1,600 years until along came Martin and the gang to set things straight...no, do it this way....no do it that way....no this is truth, ....no that is truth.....no, being Catholic is too hard, we like to sleep in on Sunday,....no, going to confession is a pain and embarrasing, ....no, music is not allowed in church...., no, statues are icons and someone probably prays to them, ....no you have to dunk someone under water to baptize them,....no, it's just bread and wine, not the body and blood of Jesus (even though He said it was)...it goes on and on...when a group of dissidents leaves any organization, they come up with a zillion reasons to justify, in their minds, why they did so....sad