Svayam-vyakta — Self-Manifested
Svayam-vyakta (Sanskrit: svayam — self/by oneself; vyakta — manifested/revealed) refers to forms or images of Bhagavān that have appeared of their own divine accord — without being carved, cast, or otherwise fashioned by human craftsmen. These self-manifested forms are held to carry a unique and extraordinary sanctity precisely because the initiative of their appearance lies with Bhagavān himself rather than with human devotion or skill.
The most widely worshipped class of svayam-vyakta forms are the śālagrāma stones — naturally occurring fossils found in the Gandaki river region of Nepal, which bear the imprints of the śaṅkha (conch) and cakra (discus) — Bhagavān's primary symbols — formed through natural processes over vast stretches of time. Because their sacred character is intrinsic and not conferred through ritual installation, śālagrāmas may be received directly into worship without elaborate consecration ceremonies.
Certain ancient temples in the Divya Dēśam tradition also house svayam-vyakta mūrtis — deity forms held by tradition to have appeared of their own will at the sacred site, often in response to the intense devotion of a particular devotee or sage. The Āzhvārs frequently celebrate svayam-vyakta deities in their pāsurams, marvelling at Bhagavān's gracious initiative in making himself available to his devotees.