Śatapatha Brāhmaṇa ("of a hundred paths") 7.1.1.28

7.1.1.28

athottarām | ayaṃ te yonirṛtviyo yato jāto arocathā ityayaṃ te yonirṛtavyaḥ sanātano yato jāto 'dīpyathā ityetattaṃ jānannagna ārohāthā no vardhayā rayimiti yathaiva yajustathā bandhuḥ

Then the northern one, with (Vâg. S. XII, 52; Rik S. III, 29, 10), 'This is thy natural womb, whence born thou shonest forth,'--that is, 'this (householder's hearth) is thy primeval, perennial womb (birth-place), whence born thou wert enkindled;'--'knowing it, ascend, O Agni, and increase our substance!' as the text, so its meaning.