After a review of the new interpretation of sex in western civilization, brought on by the scondency of the naturalistic view of life and the positivism of the modern scientist, and pointing to happiness and pleasure as the highest goal of human life, with sex the universally available source of happiness, Professor Otto A. Piper recalls his readers to a reconsideration of the Biblical view of these matters. Far from being the result of historical and social conditions alone, he would show that the modern understanding of man may be challenged and changed for the better by a true understanding of the Christian view of man. How to present such a view so that it will be considered worth trying is the problem, but Dr. Piper makes a large contribution toward this end. Believing that the Christian message will manifest its relevance only when it proclaims what no one else is saying, or is in a position to say, he forcefully and gracefully tells how the Biblical view of sex revolves around two fundamental ideas; reverence for the mystery of sex, and the sanctification of marriage. This is not a ""pious"" book that seeks to prove the point by the mouthing of platitudes. Instead, every problem that can be raised in the area of sex and marriage is objectively considered in the full light of the best that modern biological and psychiatric science can offer in the way of deepening insights, -- and then he lets the Bible say that added word that nothing else can speak. All clergy need this book. The mature layman will find it very helpful as well.