Śatapatha Brāhmaṇa ("of a hundred paths") 8.1.2.11

8.1.2.11

tā daśa-dśopadadhāti | daśākṣarā virāḍvirāḍu kṛtsnamannaṃ sarvamevāsminnetatkṛtsnamannaṃ dadhāti sarvata upadadhāti sarvata evāsminnetatkṛtsnamannaṃ dadhāti tā haitā virāja etānprāṇānbibhrati yatprāṇānbibhrati tasmātprāṇabhṛtaḥ

He lays them down by ten and ten,--of ten syllables consists the Virâg (metre), and the Virâg is all food: he thus bestows on him (Agni) the whole food. He puts them down on every side: on every side he thus bestows the whole food on him. And verily these same Virâg (verses) sustain those vital airs, and inasmuch as they sustain (bhri) the vital airs (prâna) they are called Prânabhritah.