Excerpt from the opening pages: "If there is a true spiritual life that can be lived, the great question is: Is the way open, and how can I enter into the spiritual state? Here, again, I have four short answers. "First, we must know that there is such a spiritual life to be lived by men on earth. Nothing cuts the roots of the Christian life so much as unbelief. People do not believe what God has said about what He is willing to do for His children. Men do not believe that when God says, "Be filled with the Spirit," He means it for every Christian."