Leon Morris' conclusion to his essay 'The Theme of Romans' in the F. F. Bruce festschrift:
[T]hroughout the Epistle there is a tremendous concentration on God. . . . Paul's treatment of themes like justification or sanctification or predestination have so caught the imagination of scholars and others that they have tended to concentrate on them and to overlook the dominance of the God-theme. Partly, too, this has been helped by the fact that of necessity God is prominent throughout the NT. The whole Bible is a book about God. We tend to think that Romans in this respect is just like any book in Scripture.
The point I have been concerned to make in this essay is that it is not. God comes more prominently before us in Romans than in any other part of the NT (with the possible exception of 1 John). Elsewhere Paul dwells on Christ and what Christ has done for men. This theme is not absent from Romans; but as long as we concentrate on it to the overlooking of the stress on God, we do not quite get what Paul is saying to us. Romans is a book about God and we must bear the fact in mind in all our interpretation of what it says. Otherwise we shall miss some of the wonderful things it says. (p. 263)