Śatapatha Brāhmaṇa ("of a hundred paths") 4.1.2.19

4.1.2.19

tā u ha carakāḥ | nānaiva mantrābhyāṃ juhvati prāṇodānau vā asyaitau nānāvīryau prāṇodānau kurma iti vadantastadu tathā na kuryānmohayanti ha te yajamānasya prāṇodānāvapīdvā enaṃ tūṣṇīṃ juhuyāt

Now the Karakas, forsooth, offer these two (libations) with two different formulas, saying, 'These two are his out-breathing and in-breathing: we make the out-breathing and in-breathing of varied vigour.' But let him not do this, for they disorder the sacrificer's out-breathing and in-breathing. Now, one might also offer this one silently:--