Commentaries are written explanations and interpretations of Scripture. They provide verse by verse or chapter by chapter analysis for individual books of the Bible.
One Volume Commentaries cover the whole bible in one book and provide less detail.
Multi-volume Commentary sets offer scholarly interpretation of a single Book of the Bible, or even a Chapter.
Using WorldCat, search for: bible romans commentaries or bible galations commentaries. You can narrow your search to print books or ebooks.
These well known commentaries provide verse by verse information on the scriptures.