Śatapatha Brāhmaṇa ("of a hundred paths") 1.4.5.3

1.4.5.3

viṣṇo sthānamasīti | yajño vai viṣṇustasyeva hyetadantika tiṣṭhati tasmādāha viṣṇo sthānamasītīta indro vīryamakṛṇodityato hīndrastiṣṭhandakṣiṇato nāṣṭrā rakṣāṃsyapāhaṃstasmādāheta indro vīryamakṛṇodityūrdhvo 'dhvara āsthādityadhvaro vai yajña ūrdhvo yajña āsthādityevaitadāha

Further, 'Thou art the abode of Vishnu!' Vishnu, indeed, is the sacrifice, and near to this he now stands: this is why he says, 'thou art the abode of Vishnu!'--'Here Indra performed his heroic deed;' for it was while standing in this place that Indra drove off towards the south the evil spirits, the Rakshas: for this reason he says, 'here Indra performed his heroic deed.'--'Erect stood the cult;' cult, namely, means sacrifice, hence he thereby says 'erect stood the sacrifice.'