How Many of Paul's Letters are for Us and Which are They?

There are seven Pauline letters written after he received the revelation of the mystery as set forth in Ephesians 3:  Ephesians, Philippians, Colossians, 1 & 2 Timothy, Titus, and Philemon.  These letters contain the doctrine God would have the church, which is Christ's body, learn and live by.  Consideration must be given to the fact that by the time 2 Timothy, the last of Paul's letters, was penned, even his well-established assemblies such as that at Ephesus and Colossae had turned away from his God-given authority:  "This thou knowest, that all they which are in Asia be turned away from me; of whom are Phygellus and Hermogenes."  (2 Timothy 1:15).   Since that time, fully-developed assemblies have been few and far between; with only small pockets of individual adherents guarding and teaching the knowledge of the post-Acts genesis of the "one new man" created to inherit the heavenly places.