Śatapatha Brāhmaṇa ("of a hundred paths") 6.6.2.5

6.6.2.5

mā su bhitthā mā su riṣa iti | yathaiva yajustathā bandhuramba dhṛṣṇu vīrayasva sviti yoṣā vā ukhāmbeti vai yoṣāyā āmantraṇaṃ sviva vīrayasvāgniścedaṃ kariṣyatha ityagniśca hyetatkariṣyantau bhavataḥ

[Vâg. S. XI, 68] 'Break not! Suffer not injury!'--as the text, so its meaning;--'O mother, bear up bravely!'--for the fire-pan (ukhâ, f.) is a woman; and 'O mother' is a term for addressing a woman: 'bear up well, indeed!'--(Thou) and Agni will do this (work)!'--for (the fire-pan) and Agni will indeed be doing this (sacred work).