Śatapatha Brāhmaṇa ("of a hundred paths") 1.6.3.28

1.6.3.28

etena vai devāḥ | upāṃśuyājena yaṃyamasurāṇāmakāmayanta tamupatsarya vajreṇa vaṣaṭkāreṇāghnaṃstatho evaiṣa etenopāṃśuyājena pāpmānaṃ dviṣantam bhrātṛvyamupatsarya vajreṇa vaṣaṭkāreṇa hanti tasmādupāṃśuyājaṃ yajati

By means of that low-voiced offering the gods stealing near slew, with that thunderbolt, the vashat-call, whichever they wished of the Asuras; and so does this one, after stealing near by means of that low-voiced offering, slay with that thunderbolt, the vashat-call, the wicked, spiteful enemy. This is why he performs the low-voiced offering.