In assuming a close connection between human and divine love, the mystics and the materialists join hands. With both the sexual is transmuted into the spiritual. Plato made the transition in his "Phædrus," comparing divine with human love and even with the latter in a degraded form. The sexual passion and the passion for purity both alike stir human nature to its depths, and the love of God and the love of woman are somehow akin. Religion in all ages has made free use of the imagery of love and marriage. The close connection has been emphasized by the statistics which show that the period between twelve and twenty years is preëminently the age of conversion. On the other hand, the relations between the sexual and the religious life are so various that it does not seem possible to place them in the simple relation of cause and effect. In ancient religions there were examples of phallic worship and the mutilation of priests, of temple prostitutes and vestal virgins. Polygamy and celibacy have both alike been enjoined in the name of religion. The imagery of the bride and the bridegroom has been freely used by the mystics, but it is employed as well by those who are thought to oppose religion.[122] It is true that in Christian circles the curve of conversion rises suddenly and is at its height during the adolescent period; but again the facts are not so clear as to warrant the inference that conversion is an effect of the development of the sexual life. The adolescent period is the time also of the awakening of the intellectual and æsthetic faculties, of the feeling of responsibility and the stirring of ambition. Unless all of these are irradiations of the sexual impulse, it cannot be said that the religious awakening, coming within this period, must be so regarded. The adolescent period is one of peculiar religious susceptibility, but in part this may be due to the influence of social pressure, brought to bear very strongly at this period by parents and teachers. Again, the exceptions on both sides are too many. Adolescents, even those under religious influences, are not always converted; indeed this period is one of peculiar susceptibility to doubt. It is notorious that this is the time when the Sunday-school and the church are apt to lose their hold on the boys, and the questionnaires show juvenile atheism as well as juvenile piety. Sex development cannot well be the cause both of religion and irreligion. 122: In an appreciation of the late John Davidson, it is said that "an obsession by sexual metaphors was his imaginative besetting sin."--A. S. Mories, in _Westminster Review_, July, 1913, p. 81.