A commentary is distinguished by its organization; it is a chapter by chapter, verse by verse interpretation/exposition of a biblical book.
You can search for commentaries by doing the following. In the library catalog, search by "subject" using the following format: Bible [name of book] Commentaries
The same format is used for books in both the Hebrew Bible/Old Testament and the New Testament.
For example, you can find commentaries on the Hebrew Bible/Old Testament book of Genesis by entering "Bible Genesis Commentaries."
Commentaries on the New Testament gospel of Matthew can by found by entering "Bible N T Matthew Commentaries."
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