Maitri (Maitrāyaṇīya) Upaniṣad 6.26

6.26

athānyatrāpyuktam yathā vāpsu cāriṇaḥ śākunikaḥ sūtrayantreṇoddhṛtyodare'gnau juhotyevaṃ vā va khalvimānprāṇānomityanenoddhṛtyānāmaye'gnau juhoti atastaptorvivaso'tha yathā taptorvi sārpistṛṇakāṣṭhasaṃsparśe-nojjvalatītyevaṃ vā va khalvasāvaprāṇākhyaḥ prāṇasaṃsparśenojjvalati atha yadujjvalatyetadbrahmaṇo rūpaṃ caitadviṣṇoḥ paramaṃ padam caitadrudrasya rudratvametattadaparimitadhā cātmānaṃ vibhajya pūrayatīmāṃ lokānityevaṃ hyāha
vahneśca yadvatkhalu visphuliṅgāḥ sūryānmayūkhāśca tathaiva tasya prāṇādayo vai punareva tasmād abhyuccarantīha yathākrameṇa ||

26. Now, it has elsewhere been said: ‘Verily, as the huntsman draws in fish with his net and sacrifices them in the fire of his stomach, thus, assuredly, indeed, does one draw in these breaths with *Om* and sacrifice them in the fire that is free from ill.

Furthermore, it is like a heated caldron. Now, as ghee in a heated caldron lights up by contact with [lighted] grass or wood, thus, assuredly, indeed, does he who is called non-breath light up by contact with the breaths.

Now, that which lights up is a form of Brahma, and that is the highest place of Vishṇu, and that is the Rudra-hood of

Rudra. That, having divided itself (_ātmānam_) thus unmeasured times, fills these worlds. For thus has it been said:—

And as, indeed, from fire the sparks do issue,
And likewise, too, from out the sun its light-rays,
From It repeatedly all breathing creatures
Come forth into this world, each in its order.