Which book is Paul's first book of doctrine in the New Testament?
Romans is Paul's first book of doctrine in the New Testament, at least in our New Testament. The context identifies it as the first Book of Doctrine Paul writes, and it is the place where most of our time must be spent.
Les explains that Romans is the first Book of Doctrine Paul writes, at least in our New Testament, and that is why he says we have to spend most of our time there. He contrasts this with the Gospels and the Old Testament, noting that the truth of believers becoming members of the Body of Christ comes alone from the writings of Paul. He then returns to Galatians 3:27 to show that those baptized by the Holy Spirit into the Body of Christ have put on Christ. This reinforces why Romans, as Paul's first doctrinal book, is central for understanding these Pauline truths.