Commentaries are a good way to begin studying a passage of the Bible. Many contain information on the historical setting, the author's intent, and the meaning or interpretation of the book and passage.
A good commentary is especially helpful for word studies. Scholarly and technical commentaries will always address ambiguous meanings and differing interpretations of certain Greek or Hebrew words. Popular and devotional commentaries usually won't discuss various interpretations of a word. But there are a number of commentary series that discuss technical lexical issues for readers with no Greek or Hebrew knowledge. Some of the best are these:
Chances are good that if you consult 3 or so technical or semi-technical commentaries, any difficult words or expressions will be dealt with (perhaps differently). This will give you a good indication of which words merit serious attention and which are pretty well agreed upon by all interpreters.
For more information on biblical commentaries and how to locate them, see our Biblical Commentaries guide.