I'm sure that most Bible students have heard questions similar to this one.  Indeed some even think it pointless to read the Old Testament.  Some ask innocently, others to challenge the believer.  There is no textbook answer to this type of query, but there is plenty of advice given throughout the Bible.  That, unfortunately, presents a problem for some who believe but think the bible is a well written collection of ancient literature.  For them I a truly sad. 

I answered one qustion like this:

If you won a trip to Venice and made the journey without any preparatory study understanding the attitudes and ations of people in and around Venice would be very difficult.  In fact, not knowing some of the history and tradition could even create dangerous scenarios.  Also, think about this... When new people move into your area do you immediatey accept them and tret them as if they were born there, or must you get to know them first or even void them until you know them.