There are several things you can look for without having any commentaries at all. This is called an inductive bible study. It allows the Word to speak for itself. Things to look for include
1. Key Words- usually these are words that are repetitve. If the Bible repeats itself it is usually important. Ask yourself "What is the key word here in this passage?"
2. Cause and effect statements- This looks at relationships between things. You want to look for linking words between two ideas. Words such as "because of", "since" "due to". Cause and effect statement tell us that because of one thing another happens. An example, "You are saved by grace through faith and not by works, so that no one can boast." This tells us that we are saved by grace and as a result, you may not boast about what you accomplished.
3. Promises to claim- what promise in the passage is there that you as a believe can hope in?
4. Commands- Unfortunately, we don't just have ten commandments, there are a lot of others spread throughout the Bible. Is there a command in the passage you need to respond to?
5. What does the passage tell you about the nature of God? The nature of man? Ask questions such as: Who, what, where, when, why. Let the word speak for itself.
6. Look up related text. These are often found at the end of a verse or at the bottom of the page. It can often give insight into the meaning.
7. Look at the context of the passage. That means consider where the Bible characters were and what was going on immediately before and after the verses being studied. People get into trouble when they take things out of context.
Some helpful links to study aids for the Bible
http://www.studylight.org/com/
http://www.biblestudytools.com/
http://bibleresources.bible.com/
http://www.bible.org/
