Bhagavad Gita Chapter 9.16
ahaḿ kratur ahaḿ yajñaḥ
svadhāham aham auṣadham
mantro ’ham aham evājyam
aham agnir ahaḿ hutam
Translation
But it is I who am the ritual, I the sacrifice, the offering to the ancestors, the healing herb, the transcendental chant. I am the butter and the fire and the offering.