Śivasaṃhitā 3.96

Meditation on the tongue united with prāṇa — rasanāṃ prāṇasaṃyuktāṃ vicintayet — is a somatosensory contemplation practice: the practitioner not only does khecarī but actively contemplates what is occurring. Attention turns toward the organ of taste, root of the sense that Sanskrit texts consider most intimately connected with the jīva (the individual being). Contemplating the tongue pressed against the palate is contemplating the contact point between being and prāṇa.

Prāṇasaṃyuktā (united with prāṇa) describes the tongue’s condition in advanced khecarī: not simply pressed against the palate but merged with the prānic flow circulating at that point. The meditator’s attention makes the union real: where attention goes, prāṇa goes. Contemplating the tongue united with prāṇa is directing prāṇa toward the tongue with sufficient concentration for the fusion to be real and not merely conceptual.

Vāyusiddhi — dominion of air — crowning this verse is the svastikāsana’s culmination: not the posture itself but the integrated practice of posture + contemplation + breath regulation that it enables. The wise yogin following this method obtains a body impenetrable to disease because their prāṇa flows freely, without obstruction, responding directly to consciousness’s intention.