It’s interesting that the Catholic Church teaches that anyone baptized is given the Holy Spirit, yet only those in their “apostolic line” can interpret Scripture. Jesus Himself said man was not to live on bread alone, but every word of God. If you are going to use Scripture in your actual life, you have to judge what it means and how it applies. Peter, I believe, said to be saved, we need to turn to God in repentance and believe in Jesus. A heart that has been changed to love God and submit to Him hears God’s voice and understands Scripture. Christians have disagreed over some of the lesser points, but on the most important there’s agreement. The unity among us might be better seen sometimes by unbelievers who oppose Christ and despise Christians and what they stand for.
Better first to believe in Jesus, then repent.