Skanda Purana — Mahesvara Khanda, Shloka 149
शक्तयः सर्वभावानामचिंत्या ज्ञानगोचराः । तस्मात्तत्त्वं प्रगृह्णन्ति शेषमत्रैवदृश्यते
śaktayaḥ sarvabhāvānāmaciṃtyā jñānagocarāḥ | tasmāttattvaṃ pragṛhṇanti śeṣamatraivadṛśyate
一切众生之力（Śakti）不可思议，然可由内证之智所知；故彼等摄取其要义之本原，而其余则见唯留于此。
Mahākāla
Scene: A metaphysical visualization: subtle ‘powers’ as luminous currents within beings; from an offering, a bright essence is drawn upward by unseen forces while the physical remains on the altar.
FAQs
Ritual works by śakti: subtle recipients take the ‘tattva’ (essence), while the gross remainder remains—hence visible leftovers do not negate spiritual transfer.
No tīrtha is specified; the verse concludes a general explanation of ritual mechanics.
No new prescription; it affirms the principle that offerings should be made with faith, since essence-transfer occurs through śakti.