Jaiminīya (Talavakāra) Brāhmaṇa 21.126

21.126

sa vāṃ tadanuvakṣyati
tato'pisomau bhaviṣyatha iti
tadyattadyajñasya śiro'chidyateti | so'sāvādityaḥ
sa u eva pravargyaḥ
tau ha dadhyañcamātharvaṇamājagmatuḥ
taṃ hocatur | ṛṣe upa tvāyāveti
kasmai kāmāyeti
etadyajñasya śiro'nuvakṣyāvahā iti
neti hovāca
indro vai tadapyapaśyat
sa mābravīdyadi vā idamanyasmai brūyāśśiraste chindyāmiti
tasmādbibhemīti
sa vai nāvanenāśvasya śīrṣṇānubrūhīti
tatheti hovāca
sa vai nu vāṃ saṃvadamānau paśyānīti
tau hemau svaṃ śiro nidhāyedamaśvasya śiraḥ pratisaṃdhāya tena ha sma
saṃvadamānāvāsāte sāma gāyamānāvṛcaṃ yajurabhivyāharantau
tābhyāṃ ha śraddhāya tenāśvasya śīrṣṇānuvāca

He will recite it to you two; then you will become drinkers of Soma.' As for the fact that the head of the sacrifice was cut off: that is that Āditya. And that indeed is the Pravargya. They two went to Dadhyañc Ātharvaṇa. They said to him: 'O seer, we two approach you.' 'For what desire?' 'May we two be instructed in this head of the sacrifice.' 'No,' he said, 'Indra indeed also saw that. He said to me: "If you should tell this to anyone else, I will cut off your head." Therefore I am afraid.' 'Then recite it to us two with this horse's head.' 'So be it,' he said, 'Now let me see you two conversing.' Setting aside their own heads and joining on this horse's head, they two sat conversing with it, singing a sāman and uttering a verse and a sacrificial formula. Having had confidence in them two, he recited [it] with that horse's head.