Śatapatha Brāhmaṇa ("of a hundred paths") 4.1.2.3

4.1.2.3

tamantaḥpavitrādgṛhṇāti | pratyañcamevāsminnetadudānaṃ dadhāti so 'syāyamudāno 'ntarātmanhita eteno hāsyāpyupāṃśurantaḥpavitrādgṛhīto bhavati samānaṃ hyetadyadupāṃśvantaryāmau prāṇodānau hyeteno haivāsyaiṣo 'pītareṣu graheṣvanākṣidbhavati

He draws it from inside the strainer, whereby he puts that in-breathing into him as one tending towards him, and that in-breathing of his is placed (or beneficial) within his self. And thereby also that Upâmsu (libation) of his comes to be drawn from inside the strainer (i.e. from the pure Soma), for one and the same are the Upâmsu and Antaryâma, since they are the out-breathing and in-breathing. And thereby, moreover, that (vital air) of his comes to be unceasing also at the other grahas.