Hi sabertooth,
Sooo, 'because God says not to' doesn't qualify as a 'why'?
Personally, I believe that God is actually looking to fill His kingdom with those who agree and support His authority to know what is best for us. Whether we fully understand all of the ramifications and justifications thereof, God asks us to love Him, and Jesus explains to us that such love that we should have for God, is that we obey Him. Jesus said that if we love him we will keep his commands. He didn't say that when we understand all the reasons for 'why' there are such commands, then we should keep them.
So, I find that this seemingly unquenchable thirst to know all that there is to know, or even to seek much beyond just believing and trusting in what God asks of us, leads more of us to the fruit of the tree of the knowledge of good and evil, than to the cross. After all, God seemed to think that it was sufficient just to tell Adam and Eve that eating of the fruit would bring death, without having to spend a book full of explanations as to 'why' eating from the tree of the knowledge of good and evil would bring death.
Those are some of my thoughts on our feeling like we need to understand more than God's word tells us in explanation of things. God wants us to trust Him, despite our individual abilities to understand a lot of the 'why' we should trust Him. The born again believer trusts God because he/she does understand that God loves us and no matter what He tells us, He has our best interests at heart.
My encouragement is that if you really can accept God's word just saying "Do this" and "Don't do that", that's really all God is looking for, and in most cases, is all that God gives us.
God bless,
In Christ, ted