Śatapatha Brāhmaṇa ("of a hundred paths") 8.7.2.3

8.7.2.3

saiṣaikaiva bhavati | ekasthaṃ tatkṣatramekasthāṃ śriyaṃ karotyatha yā dvitīyā mithunaṃ tadardhamu haitadātmano yanmithunaṃ yadā vai saha mithunenātha sarvo 'tha kṛtsnaḥ kṛtsnatāyā ekena yajuṣā bahvīriṣṭakā upadadhāti kṣatraṃ tadvīryeṇātyādadhāti kṣatraṃ viśo vīryavattaraṃ karotyathetarāḥ pṛthaṅnānā yajurbhirupadadhāti viśaṃ tatkṣatrādavīryatarāṃ karoti pṛthagvādinīṃ nānācetasam

Now this is only a single (brick): he thus makes the nobility (or the chieftaincy) and (social) distinction to attach to a single (person). And what second (such brick there is) that is its mate,--a mate, doubtless, is one half of one's own self, for when one is with a mate then he is whole and complete: (thus it is laid down) for the sake of completeness. With a single formula he lays down many bricks: he thereby endows the nobility preeminently with power, and makes the nobility more powerful than the peasantry. And the other (bricks) he lays down singly, with separate formulas: he thereby makes the peasantry less powerful than the nobility, differing in speech, and of different thoughts (from one another).