Śatapatha Brāhmaṇa ("of a hundred paths") 1.3.3.14

1.3.3.14

sa hovāca | vajro vai tānvaṣaṭkāraḥ prāvṛṇagvajrādvai vaṣaṭkārādbibhemi yanmā vajro vaṣaṭkāro na pravṛñjyādetaireva māparidhatta tathā mā vajro vaṣaṭkāro na pravarkṣyatīti tatheti tametaiḥ paryadadhustaṃ na vajro vaṣaṭkāraḥ rāvṛṇaktadvarmaivaitadagnaye nahyati yadetaiḥ paridadhāti

He then said, 'The thunderbolt, (in the shape of) the vashat-call, has struck these down: I am afraid of that thunderbolt, the vashat-call. Lest that thunderbolt, the vashat-call, should strike me down, enclose me by those (three Agnis, or paridhis); and thus that thunderbolt, the vashat-call, will not strike me down.' They said, 'So be it!' and they enclosed him with those (three sticks), and that thunderbolt, the vashat call, did not strike him down. When he encloses Agni with those (sticks) he buckles armour on him.