Kauṣītaki (Śāṅkhāyana) Brāhmaṇa 1.4.13

1.4.13

svapiti iva vā etasya agnir yo agmim udvāsayate /

fire of him who removes the fire is asleep as it were, verily so does he again awaken it.’ But that connected with the slaying of Vṛtra is the approved one. ‘O Agni, thou purifiest lives’ is the invitatory verse of the second (butter-portion). ‘Thou purifiest’ is the symbol of Soma, for the sacrificial offering is wholly for Agni; in that he makes mention of the purifying, so he departs not from the butter-portion for Soma. The offering and the invitatory verses are Padapaṅktis; the Paṅkti has five feet; the sacrifice is fivefold; verily (they serve) to obtain the sacrifice.