Lewis begins this book describing two different terms, making and begetting. He says that those who are made have a biological life and are later given a spiritual life by the only one who has that sort of life, God himself. The Bios life, as Lewis calls it, is “a certain shadowy or symbolic resemblance to Zoe” (or Spiritual life.) Because we were made with free will and choose to deny God, it is now impossible in order to become Sons of God on our own. Instead, we must embrace the death of this life and the beginning of a new and eternal life.
When God made Adam, He made him in the likeness of Himself. This is different than begetting. The only begotten Son of God is Jesus. If God made man then man cannot be a god of any sort (a point that Lewis makes then later overlooks). An image Lewis paints of this is like a man sculpting a statue. The statue has all the resemblance of a man, but absolutely no ability to think or move or reason on it’s own.
So, at one point in history man had the ability to be sons of God, they had a spiritual life. A brief period of time man was in perfect communion with God, and his wife for that matter. Now, we have lost the spiritual life and it only makes sense that we would need the one who has Zoe to cross over into the Bios. In fact it is the only thing that would make sense. What Jesus came into the world to do was not show us how to be more religious or how to re-awaken our sleeping spiritual life. He came to take what was dead and make it alive. Just as a person who has drowned cannot administer his or her own CPR, so is people who are spiritually dead cannot on their own resurrect themselves. They must be born again.
Now that Book 4 is done and I reflect back I don’t remember seeing any direct quotes from the Bible (probably because he didn’t believe in the inerrancy of scripture). This is what I believe to be one of Lewis’ biggest flaws and greatest attributes. It is one of his great attributes because it shows that Christianity can be reasoned even in common knowledge of reality. But, it is one of his greatest flaws because instead of making a biblical defense for Jesus, he subjects himself to his own opinions of what Christianity truly is (which is why we must believe in and use the Bible).
Also looking back I don’t think it wise that anyone should attempt to explain something as complex as Christianity without addressing the controversies. Anything that has been debated amongst Christians has been debated for a good reason. He spoke quite a bit about free will and never such as mentions predestination or God’s elect, which are actual terms used in the Bible. That has been one of the greatest debates amongst Christians for the last few centuries.
All of that being said I do love Lewis. Despite the disagreement I would have with him on nearly every point of theology, he reads and understands scripture in an amazing way. And his understanding of joy that comes from faith in Christ is amazing.