It's not about dealing with anything. It's purely that God is the Akmighty Creator of this world. And when he made the first humans, (along with everything else) He gave them a free will. The only rule that God gave Adam and Eve was to not eat the fruit off of one single tree. And they would have rather sinned and eaten the fruit rather than, live in forever happiness and purity.

Humans have been givin the choice to live as they want. God isnt going to interfere with what you choose to do, but once you die your going to be asked why you did what you did. And if you deliberatly disobeyd God then your going to hell.

Another thing, and which is the most important in Christianity is Faith. You have to Believe in what God has said and done. The Bible was wrote by a miracle of God, thats what how he wanted it to be done. He gives the message to a holy person and they relay it into a book. If you dont have faith in something, then your living for nothing.