That there exists a relationship between the cultivated ethical emotion, religious feeling, and the essentially natural physio-psychical function, sexual desire or _libido_, is a fact noticed and commented on by many thinkers and writers. The literature of the subject is, however, exceedingly fragmentary and disconnected, no author (as far as I have been able to determine) having devoted as much as one thousand words to the consideration of this very interesting psychical phenomenon. Hence, my data have been gathered from many sources, which are as diversified as they are numerous. Beyond a question of doubt, man becomes religiously enthused most frequently either early in life, when pubescence is, or is about to be, established, or late in life, when sexual desire has become either entirely extinct or very much abated. Young boys and girls are exceedingly impressionable at, or just before, puberty, and are apt to embrace religion with the utmost enthusiasm. A distinguished evangelist declares that "men and women seldom or never enter into the kingdom of God after they have arrived at maturity. Out of a thousand converts, seven hundred are converted before they are twenty years old."[92] [92] B. Fay Mills, _Sermon to Young Men and Young Women_, at Owensboro, Ky., May 20, 1894. The Roman Catholic church is keenly alive to these facts, therefore requires the rite of confirmation to be administered, if possible, to its would-be communicants at, or before, the age of puberty.[AE] [AE] This knowledge is not confined to the Catholic church alone; in all denominations the pubescent human being is considered most susceptible to religious influences. The cause or _raison d 'etre_ of this susceptibility is, by no means, generally recognized.