God has worked through His earthly spokesmen all throughout history. Some examples are Noah to the pre-flood world, Moses and the prophets during the Old Testament (OT) dispensation of the Law, and Jesus Christ Himself when He came to earth 2,000 years ago. Today, God’s spokesman to us is the apostle Paul – the apostle of the Gentiles (Rom. 11:13; Gal. 2:7-9; 1 Tim. 2:7; 2 Tim. 1:11). He preaches the applicable gospel (Rom. 16:25; Gal. 1:6-9, 11-12; 1 Tim. 1:11) and doctrine (2 Tim. 3:10-14) for the present “dispensation of the grace of God” and we are to follow him (1 Cor. 4:16; 11:1; Php. 3:17; 2 Thess. 3:7,9). The mystery of the Body of the Christ was not revealed to any of the OT prophets nor to any of Christ’s disciples when He was here on earth. Jesus Christ revealed this mystery ONLY to Paul after He was risen and ascended back to heaven (Eph. 3:2-5).
Of course, Paul is not our god and he does not have dominion over our faith; he makes that very clear (2 Cor. 1:24). However, Christ speaks through his written epistles directly to us and Paul is our ensample, our pattern (1 Tim. 1:12, 13-16). To properly understand the Bible, it is key for us to “rightly divide the word of truth” (2 Tim. 2:15) and first determine what is written TO US, the Body of Christ. In our case, it is Paul’s 13 epistles of Romans through Philemon. The remainder of the Bible then falls into place and we read those parts for “learning” and “admonition” (Rom. 15:4; 1 Cor. 10:11). All scripture is profitable (2 Tim. 3:16-17) but not all scripture is written TO US.