To a church that he had never met, Paul wrote his longest and most systematic letter. It is a magisterial masterpiece—preeminent among the writings of the apostles. It has been called “the profoundest book in existence,” “the cathedral of the Christian faith,” and “the quintessence and perfection of saving doctrine.” What most centrally distinguishes this letter? That which breaks into its opening words. More than merely introducing himself, relating to his recipients, and identifying his purpose for writing, Paul begins emphatically with the basics of the gospel of God. Here, his chief passion leaps out of his greeting. Indeed, the very heart of this great letter is summarized in the wonderful essentials of the gospel of God.