Paul was a very fallible man the same as you or me. He is not a part of the Trinity, is not God and is not the final authority for anything, no matter what your pastor or Church might tell you.
Other Pauline doctrines addressing the issue are found in Ephesians 6:10-20 which might help place our duty in appropriate light.
While Paul might not be a final authority, where he was inspired by God the Holy Spirit to communicate His Word and the mind of Christ, the authority of Christ does have veracity in the Pauline epistles. Read Eph 3, while in fellowship with Him through faith in Christ, with close attention to Eph 3:9-13 for further clarification.