Christians...Why does Bible support violence?

I would like to say first off that the Quran is of the Muslim belief not the Christian belief. Secondly, God always separates the good from the evil as Christ was the prime example of this. Jesus said, the greatest love is to lay down your life for a friend. Jesus laid down his life for us, we are his friends. What is a friend if he will turn his back on you. Its all a big test! Are you showing your love of God's children or would you turn your back on someone in need? Do you love others so much that you are willing to suffer for someone else?