An interpretive hypothesis must be judged finally according to its explanatory power with respect to the parts as well as the whole of a given literary work. I argue that Romans is a protreptic writing seeking to affirm Paul's ministry and the gospel which he preached. In recent years, sections of the genuine Pauline epistles (especially 1 and 2 Cor.), and even entire epistles have been considered to be self-apologies wherein Paul defends his apostleship. This restriction of the use of the term apology to a self-defense, however, is not justified by the ancient sources for the most characteristic Jewish Hellenistic apologies were propaganda on behalf of the Law rather than the author's defense against personal accusations. Further, the undisputed Christian apologetic writings of the second century are not primarily defenses but positive propagandistic appeals to win converts to the new movement. These writings fulfill the same function as do philosophical Protreptics. Genre criticism, albeit important, should be complemented by analysis of content. In considering the material content of Romans, I have employed motif analysis as the primary method. This approach was chosen over, on the one hand, word analysis which is often too restrictive and may as readily obfuscate as elucidate an author's intent; and on the other hand, a thematic analysis that may promote sweeping conceptual generalizations which however intriguing may again have little to do with an author's intended meaning.