From Schreiner on Paul’s Mission:

“With the exception of Romans [I don’t think I totally agree with this exception] most of Paul’s remaining letters were written to maintain the faith of those who had joined the new community, for persistence in faith was the mark of a successful mission. . . . Paul had no conception of his mission advancing apart from the proclamation of the gospel, and thus we see again that the missionary and theological task of Paul are indissoluble” (64).

“Wherever the gospel is preached, fruit is the inevitable consequence, for the prolcaimed word is a performative word, accomplishing what it demands” (65).

“Faith is not a private reality that arises from inner reflection or as a result of philosophical investigation” (65).

“. . . the Pauline emphasis on perseverance indicates that simply laying a foundation was not sufficient.  He did not believe his work as an apostle was accomplished unless both the churches were established and they persevered” (66-67).

“It is likely, therefore, that preaching the gospel (euangelizomai) and “gospel” (euangelion) in Paul cannot be confined to the initial proclamation of the message.  We have already seen that the gospel involves the obedience of faith (Rom 1:1-5; 16:25-27); and this obedience of faith cannot be restricted to conversion but is borne out by perseverance.  Under the umbrella of the gospel is every aspect of Christian existence, for Philippians 1:27 calls on believers ‘to live in a manner worthy of the the gospel of Christ'” (67).

Schreiner believes that the mentionof Euodia and Syntyche in Philippians 4:3 is evidence that they were preaching the gospel to women.  He offers no corroborating support.  Seems more speculation than substance here (68).
“Paul avoids formulating a specific pattern for relating to unbelievers.  Life is too complex and situations are too varied to enforce preset formulas.  Accordingly, he prays for wisdom in relating to unbelievers” (69).

“Paul’s ultimate goal, however, was not his mission. . . . The reason he engaged in mission was for the sake of the name of Jesus Christ, to see him exalted so that every knee would bow and every tongue confess him as Lord (Phil 2:10-11)” (71).