Bengal, India, ca. 1650
The Yoni Tantra is a sacred text from Bengal (16th century) mainly concerned with describing the Yoni Puja, or "Mass of the Vulva"; one of the secret and esoteric Tantric rituals dedicated to creating - and consuming - the sacred fluid that is called yonitattva (Skt., yoni substance).
According to this text, sexual union (mithunam) is an indispensable part of Tantric ritual and may be performed by and with women between the age of twelve and sixty years, married or not, except for a girl not yet menstruating. The text specifies nine types of women (navakanya) who may perform these rituals, yet explicitly forbids an incestuous mother/son constellation.
In general, however, this Tantra does not impose many restrictions on the practitioner (Skt., sadhaka) who is dedicated to the Yoni Puja. It advocates use of the five makara and leaves the choice of partner, place and time very much up to the practitioner. Nevertheless, the male sadhaka is explicitly admonished "never to ridicule a yoni" and to treat all women well and never to be offensive toward them.
In the two quotes below, it becomes clear just why the text bears its name, showing that the yoni is truly the center of worship.
Meditate as being absorbed in the yoni cakra,
with yoni on the tongue,
yoni in the mind,
yoni in the ears
and yoni in the eyes.
All sadhana is vain unless with the yoni.
Yoni Tantra, Patala 10
The practitioner who utters the words Yoni Yoni
at the time of his prayers,
for him the Yoni shall be favourable,
granting him enjoyment and liberation.
Yoni Tantra, Patala 3
J.A. Schoterman. The Yonitantra. New Delhi: Manohar, 1980.
Michael Magee (trans). Yoni Tantra. Azoth Magazine #16-19, 1985.