The view of sex as a sacred mystery is one which can be traced at various levels of sophistication. In its most primitive form, the sexual act is seen merely as having powerful magic properties. Essentially, the principle behind magic is that of sympathetic action: in order to make the wind arise, one whistles; in order to make the corn grow high, one leaps into the air; in order to kill one’s enemy, one sticks pins into his effigy. At that dark season of the year, when all nature seems dead, what should one do to ensure that the seeds in the ground shall quicken and new growth appear ? What but perform the sexual, generative act oneself. Thus, in earliest times, and among many preliterate peoples today, we often find the sexual act as the cumulating point of a ceremony of rebirth, a ceremony usually performed either at midwinter, on the day following the shortest day, or (where less astronomical knowledge exists) at the moment when winter turns into spring. Even in modern times, in the remoter parts of Europe, peasants would go to the fields to copulate with each other, in order to ensure a good crop.
Primitive man’s wealth and security depends upon the fertility of his crops and herds, and upon a supply of sons and daughters to help him in the tasks of agriculture: how can he look upon fertility but as a blessing, bestowed when God is favourably inclined, withheld when He is angry. The sexual organs serve as a symbol to remind man that all depends upon this vital process, they are the vehicle of the sacred generative power. And so, in the earliest days of Rome and Greece, we find phalli exhibited outside shops, baked in pastry, hung round children’s necks, and, above all, exhibited at places of Worship or carried in procession, just in the same way, and for much the same reasons, that the Cross is exhibited in Christian periods. (160)
In earliest times, God is not conceived in human or personalized form, but as soon as He emerges as a quasi-human figure it is natural to regard Him as ultimately responsible for this generative magic; hence the idea develops that all fertilisation is caused by the god himself — the man is merely the vehicle. In many mythologies, it is the moon which fertilizes — hence the reluctance of sleeping women to let the moonlight fall upon them — and among those tribes which are beginning to discover the role of the man in conception, the explanation is added that the man “opens the way” for the moonbeams. (122) At a later stage, when astronomical knowledge has advanced, the sun may become the male, fertilizing figure and the moon changes from a male to a female deity. In the animistic phase of religion, when every tree and river has its local indwelling spirit, we find maidens bathing in the river and symbolically offering their virginity to the river god.
While this idea obtains, all births are virgin births, in the sense that no man, but a god, is responsible for them. In a later phase, folk memories of this persist, and culture heroes often claim to be descended from the union of a woman and a god, usually the moon. Genghis Khan made this claim: and Isaiah was made by his translators to assert that the Messiah who was to save Israel would be born in a similar manner. Later, Christ was credited with virgin birth not because it was thought miraculous — it was not — but because it was the standard way of claiming special importance. (122)