The ethos of the book is very much shaped by the quote below from Elton Trueblood.
The Strategy of Jesus
Jesus was deeply concerned for the continuation of his redemptive work after the close of His earthly existence, and His chosen method was the formation of a redemptive society. He did not form an army, establish a headquarters, or even write a book.
All he did was to collect a few unpromising men and women, inspire them with the sense of His vocation and theirs, and build their lives into an intensive fellowship of affection, worship, and work. One of the truly shocking passages of the gospel is that in which Jesus indicates that there is absolutely no substitute for the tiny redemptive society. If this fails, He suggests, all is failure; there is no other way. He told the little bedraggled fellowship that they were actually the salt of the earth and that if this salt should fail there would be no adequate preservative at all. He was staking all on one throw.
What we need is not intellectual theorizing, or even preaching, but a demonstration. There is only one way of turning people’s loyalty to Christ, and that is by loving others with the great love of God. We cannot revive faith by argument, but we might catch the imagination of puzzled men and women by an exhibition of a fellowship so intensely alive that every thoughtful person would be forced to respect it.
If there should emerge in our day such a fellowship, wholly without artificiality and free from the dead hand of the past, it would be an exciting event of momentous importance. A society of loving souls, set free from the self-seeking struggle for personal prestige and from all unreality, would be something unutterably precious. A wise person would travel any distance to join it.