Śivasaṃhitā 4.81

The first part of the verse describes the initial phase of advanced Vajrolī: the absorption of the feminine fluid (rajas) as a catalyst of internal transmutation. The term sudhī (‘the one of pure intellect’) signals that this practice is not hedonic in nature but alchemical: the practitioner seeks not pleasure but the union of the two cosmic principles in their own subtle body.

Rajaḥ striyo yonyāḥ — ‘the fluid from the woman’s womb’ — is the śakti-tattva in its densest form: solar-active energy concentrated in the feminine secretion. Vidhivat (‘according to the proper method’) is the technical guarantee that the process is not improvisation but a precise sequence received from the guru. Retention of one’s own bindu (svakaṃ binduṃ sambandhya) is the sine qua non condition: without seminal control, the absorption of the feminine fluid cannot complete its alchemical function.

The second part of the verse — the closing of the cycle of the ten mudrās — is one of the chapter’s most solemn statements: none of the ten has an equal in the past or future. This atemporal superiority (na babhūva na bhaviṣyati) establishes the system’s completeness: these are not techniques that will be surpassed by subsequent developments but the definitive expression of the tantric hatha yoga methodology. The guarantee of siddhi through any one of them (ekatareṇa api) underscores the sufficiency of each practice individually.