The retention of sperm:

For a Buddhist Tantric, the retention of the male seed is the sine qua non of the highest spiritual enlightenment. This stands in stark opposition to the position of Galen (129–199 C.E.), the highest medical authority of the European Middle Ages. Galen was of the opinion that the retentio semenis would lead to a putrefaction of the secretion, and that the rotten substance would rise to the head and disturb the functioning of the brain.

In contrast, the tantras teach that the semen is originally stored in a moonlike bowl beneath the roof of the skull. As soon as a person begins to experience sexual desire, it starts to flow out, drop by drop, passing through the five energy centers (chakras). In each of these the yogi experiences a specific “seminal” ecstasy (Naropa, 1994, p. 191). The destination of the sperm’s journey within the body is the tip of the penis. Here, through extreme meditative concentration, the adept collects the lust: “The vajra [penis] is inserted into the lotus [vagina], but not moved. When lust of a transient art arises, the mantra hum should be spoken. ... The decisive [factor] is thus the retention of the sperm. Through this, the act obtains a cosmological dimension ... It becomes the means of attaining enlightenment (bodhi)” (Grönbold, Asiatische Studien, p. 34). “Delight resides in the tip of the vajra [penis]", as is said in a Kalachakra text (Grönbold, 1992a).

With the topic of sperm retention, an appeal is made to ancient Indian sexual practices which date from pre-Buddhist times. In the national epic poem of the Indians, the Mahabharata, we can already read of ascetics “who keep the semen up” (Grönbold, Asiatische Studien, p. 35). In early Buddhism, a holy man (Arhat) is distinguished by the fact that his discharges have been conquered and in future no longer occur. From Vajrayana comes the striking saying that “A yogi whose member is always hard is one who always retains his semen” (Grönbold, Asiatische Studien, p. 34). In contrast, in India the flowing of the male seed into “the fiery maw of the female sexual organ” is still today regarded as a sacrificium, and therefore feared as an element of death (White, 1996, p. 28.

The in part adventurous techniques of semen retention must be learnt and improved by the adept through constant, mostly painful, practice. They are either the result of mental discipline or physical nature, such as through pressure on the perineum at the point of orgasm, through which the spermatic duct is blocked, or one stops the seminal flow through his breathing. If it nonetheless comes to ejaculation, then the lost sperm should be removed from the mudra’s vagina with the finger or tongue and subsequently drunk by the practitioner.

Yet that which is forbidden under penalty of dreadful punishments in hell for the pupil, this is not by a long shot the case for his guru. Hence, Pundarika, the first commentator upon the Kalachakra Tantra, distinguishes between one “ejaculation, which arises out of karma and serves to perpetuate the chain of rebirth, and another, which is subject to mental control ...” (Naropa, 1994, p. 20). An enlightened one can thus ejaculate as much as he wishes, under the condition that he not lose his awareness in so doing. It now becomes apparent why the vajra master in the second higher initiation (9) of the Time Tantra is able to without harm let his sperm flow into the vagina of the mudra so as to be able to offer the mixture (sukra) which runs out to the pupil as holy food.

The sukra

In the traditional Buddhist conception an embryo arises from the admixture of the male seed and the female seed. This red-white mixture is referred to by the texts as sukra Since the fluids of man and woman produces new life, the following analogic syllogism appears as obvious as it is simple: if the yogi succeeds in permanently uniting within himself both elixirs (the semen virile and the semen feminile), then eternal life lies in store for him. He becomes a “born of himself”, having overcome the curse of rebirth and replaced it with the esoteric vision of immortality. With the red-white mixture he attains the “medicine of long life”, a “perfected body” (Hermanns, 1965, pp. 194, 195). Sukra is the “life juice” par excellence, the liquid essence of the entire world of appearances. It is equated with amrta, the “drink of immortality” or the “divine nectar”.

Even if many tantric texts speak only of bodhicitta, the male seed, at heart it is a matter of the absorption of both fluids, the male and the female, in short — of sukra. Admittedly the mixing of the sexual fluids does seem incompatible with the prohibition against ejaculation, but through the so-called Vajroli method the damaging consequences of the emission of semen can be reversed, indeed this is considered a veritable touchstone of the highest yogic skill. Here, the tantra master lets his bodhicitta flow into his partner‘s vagina in order to subsequently draw back into himself through his urethra the male-female mixture which has arisen there. “After he has streamed forth,” Mircea Eliade quotes a text as saying, “he draws in and says: through my force, through my seed I take your seed — and she is without seed” (Eliade, 1985, p. 264). The man thus steals the seed of the woman under the impression that he can through this become a powerful androgynous being, and leaves her without her own life energy.

Some of the “initiated” even succeed in drawing up the semen feminile without ejaculating any sperm so as to then produce the yearned-for sukra mixture in their own body. The mastery of this method requires painful and lengthy exercises, such as the introduction of small rods of lead and “short lengths of solder” into the urethra (Eliade, 1985, p. 242). Here can be seen very clearly how much of a calculating and technical meaning the term upaya (method) has in the tantras. Yet this does not hinder the Tantric Babhaha from celebrating this thieving process in a poetic stanza:

In the sacred citadel of the vulva of
a superlative, skillful partner,
do the praxis of mixing white seed
with her ocean of red seed.
Then absorb, raise, and spread the nectar—
A stream of ecstasy such as you’ve never known.
(quoted by Shaw, 1994, p. 158).

Ejaculation:

Now what happens if the yogi has not mastered the method of drawing back? Fundamentally, the following applies: “Through the loss of the bindu [semen] comes death, through its retention, life” (Eliade, 1985, p. 257). In a somewhat more tolerant view, however, the adept may catch the sukra from out of the vagina in a vessel and then drink it (Shaw, 1994, p. 157). It is not rare for the drinking bowl to be made from a human skull. The Candamaharosana Tantra recommends sucking the mixture up with a tube (pipe) through the nose (George, 1974, p. 75). If one sips the sukra out of his mudra’s genitals with his mouth, then the process is described as being “from mouth to mouth” (White, 1996, p. 200). Without exaggeration one can refer to this drinking of the “white-red bodhicitta” as the great tantric Eucharist, in which semen and blood are sacredly consumed in place of bread and wine. Through this oriental “Last Supper” the power and the strength of the women are passed over to the man.

-- "The Shadow of the Dalai Lama," by Victor and Victoria Trimondi