The catholic ideology combines the OT and the Gospel to see God. I do not believe that the OT fathers saw the true God, but an unclear, void influenced by the darkness provided by the false god (devil, Satan, Demiurge, etc.). The catholic thought is an "all in one" religion, where the priests dictate celestial authority, ie Gods representatives on Earth. I don't see it. Jesus Christ was the light in such darkness. The early catholics wanted authority over Christian and Jew alike. It's roots stem from the Pharisee's who would accept some of Christ as long as they could still have the power over man that they had prior to Christ.
Galatians addresses this in clarity, and shows how Peter fell for the combo ideology. This is further explained in the Incident at Antioch with Peter and Pauls disagreements. Peter went one way, Paul the other. The catholics followed Peter. The Gospels clearly point to the one disciple who had problems in understanding. Peter. But the catholicc were misled by one verse. The rock.
Peter was constantly being corrected for his "flesh" views over spirit. And the catholic ideology became the church Rome (Constantine) accepted due to it's fleshly allowances. Constantine could still be wealthy and murder because the authority allowed it and even used it themselves for the power of "good".
Paul went on to teach gnosis, what the gnostics followed. Valantinus saw the corruption of the catholic ideology first hand and left it. So did those like Marcion. Both dropped the OT teachings in favor of continuing books related to what the Spirit (capital S) was teaching, over the old books before the Spirit was given.
The church fathers were priests that had great power. Eventually, that power reformed Pauls teachings of gnosis as well as Johns, to be subject to the authority of the old books that gave the power of flesh to men of authority.
The only way to see this chasm from two gods, two directions, is to seek out the big picture of both sides, and let the Spirit reveal to you where it is. If you are raised in one thought only, and think that men before you must have been correct since there were so many on the same path, you may want to reread the Gospel message about the wide road and narrow one. If you seek within the Bible (only), you are going to see what the catholics see. If you expand to seeking beyond their church, you may be amazed at what you thought was Christian, wasn't seen in the fruits they provided.
You only have one life to make sure. I continue to look under every stone to either be more strengthened or to adjust where the Spirit shows me to adjust. "It is finished" when we draw the last breath.
Just my thoughts. Being a Christian is being anointed with the Spirit, understanding it and following it. Religions of men mean nothing. A Christian is a Christ. A son of God. Spiritually. They rise above religions.