Rāja-Vidyā-Rāja-Guhya Yoga · Verse 16
अहं क्रतुरहं यज्ञः स्वधाहमहमौषधम् | मन्त्रोऽहमहमेवाज्यमहमग्निरहं हुतम्
ahaṃ kratur ahaṃ yajñaḥ svadhāham aham auṣadham | mantro 'ham aham evājyam aham agnir ahaṃ hutam
I am the ritual, I am the sacrifice, I am the oblations, I am the medicine, I am the mantra, I am the clarified butter, I am the fire and I am the act of offering.
A declaration of complete identity between the Lord and all elements of the Vedic sacrifice. Kratu are the extensive rituals; yajña the general sacrifice; svadhā the oblations to ancestors.
Auṣadham includes all medicinal remedies, especially the sacred plants used in rituals. Ājyam — clarified butter or ghee — is the essential fuel of ceremonial fires.
Agni (fire) and hutam (the act of offering) complete the identification: the Lord is both the instrument and the action. The sacrifice is, in essence, the Lord worshipping Himself through the devotee.