Shatapatha Brahmana 6.5.3.1

6.5.3.1

tasyā etasyā aṣāḍhām pūrvāṃ karoti | iyaṃ vā aṣāḍheyamu vā eṣāṃ lokānām prathamāsṛjyata tāmetasyā eva mṛdaḥ karotyeṣāṃ hyeva lokānāmiyam mahiṣī karoti mahiṣī hīyaṃ tadyaiva prathamā vittā sā mahiṣī

Of that same (clay) she (the queen) forms the first, the 'invincible' (brick); for the invincible one (Ashâdhâ) is this earth, and this earth was created first of these worlds. She forms it of that same clay, for this earth is (one) of these worlds. The (Sacrificer's) consecrated consort (mahishî) forms it: for this earth is a 'mahishî' (female buffalo, a cow). She who is first taken to wife is the consecrated consort.