Śatapatha Brāhmaṇa ("of a hundred paths") 4.5.7.3

4.5.7.3

tā haike | yajñatanva ityācakṣate yajñasya ha tvevaitāni parvāṇi sa eṣa yajñastāyamāna etā eva devatā bhavanneti

Now some call these (formulas) the 'forms of the sacrifice;' but, indeed, they are rather the joints of the sacrifice: this same sacrifice, in being performed, is continually becoming those deities.