In addition to Bible commentaries, a number of other tools are helpful for doing Bible study and exegesis. These include concordances, Bible dictionaries and encyclopedias, atlases, Old and New Testament introductions, Old and New Testament theologies and resources on Old and New Testament literature and background.
Denver Seminary lists some of these tools on the following pages:
Annotated Old Testament Bibliography
New Testament Exegesis Bibliography
Bible study tools published from about 1960 to about 2010 can be borrowed online at archive.org. I have made a list of some of them here: Bible Study Tools to Borrow.
The website Bible Study Tools has older Bible concordances, dictionaries and encyclopedias online. You can find Bible concordances here, Bible dictionaries here and Bible encyclopedias here.
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