Vaishnava Dharmashastra 1.8

1.8

dakṣiṇāhṛdayo yogamahāmantramayo mahān
upākarmoṣṭharuciraḥ pravargyāvartabhūṣaṇaḥ //

His heart was the sacrificial fee; he was possessed of the (sacrificial and other) great Mantras employed in order to effect the union of the mind with the Supreme; he was of enormous size (like the long sacrifices lasting more than one day); his lovely, lips were the beginnings of the two hymns recited at the beginning of the animal sacrifice; his ornaments were the whirlpool of the milk poured into the heated vessel (at the Pravargya ceremony introductory to the Soma-sacrifice).