Understanding the Tools we use for bible study

Going beond the one volume commentary is the critical commentary.   These are usually published in one or two volumes per book of the bible.   They will have a vast range of theological perspective and you will need to have somethign of an understanding of where the author is coming from.  i.e.  conservative, radical, modern, liberal, universal etc.

That being said there is a point in the study where a reading of all the commentaries that you can get your hands on will give you an idea of every interpretation that has ever been made of the passage under study.   

If your interpretation does not fall somewhere on the continum then you might want to check your work.