Shatapatha Brahmana 8.1.1.6

8.1.1.6

vasiṣṭha ṛṣiriti | prāṇo vai vasiṣṭha ṛṣiryadvai nu śreṣṭhastena vasiṣṭho 'tho yadvastṛtamo vasati teno eva vasiṣṭhaḥ prajāpatigṛhītayā tvayeti prajāpatisṛṣṭayā tvayetyetatprāṇaṃ gṛhṇāmi prajābhya iti prāṇam purastātprāpādayata nānopadadhāti ye nānākāmāḥ prāṇe tāṃstaddadhāti sakṛtsādayatyekaṃ tatprāṇaṃ karotyatha yannānā sādayetprāṇaṃ ha vicindyātsaiṣā trivṛdiṣṭakā yajuḥ sādanaṃ sūdadohāstattrivṛttrivṛdagniryāvānagniryāvatyasya mātrā tāvattatkṛtvopadadhāti

'The Rishi Vasishtha,'--the Rishi Vasishtha, doubtless, is the breath: inasmuch as it is the chief (thing) therefore it is Vasishtha (the most excellent); or inasmuch as it abides (with living beings) as the best abider (vastri), therefore also it is Vasishtha.--'By thee, taken by Pragâpati,'--that is, 'by thee, created by Pragâpati,'--'I take breath for my descendants (and people)!'--therewith he introduced the breath from the front. Separately he lays down (these ten bricks): what separate desires there are in the breath, those he thereby lays into it. Only once he settles them: he thereby makes it one breath; but were he to settle them each separately, he assuredly would cut the' breath asunder. This brick is trivrit (threefold): the formula, the settling, and the sûdadohas, that is threefold, and threefold is Agni,--as great as Agni is, as great as is his measure, so much he lays down (on the altar) by so dying.