Shatapatha Brahmana 6.3.1.1

6.3.1.1

etadvai devā abruvan | cetayadhvamiti citimicateti vāva tadabruvaṃsteṣāṃ cetayamānānāṃ savitaitāni sāvitrāṇyamapaśyadyatsavitāpaśyattasmātsāvitrāṇi sa etāmaṣṭāgṛhītāmāhutimajuhottāṃ hutvemāmaṣṭhadhāvihitāmaṣāḍhāmapaśyatpuraiva sṛṣṭāṃ satīm

The gods then said, 'Meditate ye!' whereby doubtless they meant to say, 'Seek ye a layer!' Whilst they were meditating, Savitri saw those Sâvitra (formulas); and inasmuch as Savitri saw them, they are called Sâvitra. He offered that eightfold-taken libation; and when he had offered it, he saw this eightfold-appointed Ashâdhâ, which had been created aforetime.