Śatapatha Brāhmaṇa ("of a hundred paths") 3.8.3.28

3.8.3.28

amurā ha vā agre paśumālebhire | taddevā bhīṣā nopāveyustānheyam pṛthivyuvāca maitadādṛḍvamahaṃ va etasyādhyakṣā bhaviṣyāmi yathā yathaita etena cariṣyantīti

Now the Asuras, in the beginning, seized a victim. The gods, from fear, did not go near it. The Earth then said unto them, 'Heed ye not this: I will myself be an eye-witness thereof, in whatsoever manner they will perform this (offering).'