Shatapatha Brahmana 11.4.1.1

11.4.1.1

uddālako hāruṇiḥ udīcyānvṛto dhāvayāṃ cakāra tasya niṣka upāhita āsaitaddha sma vai tatpūrveṣāṃ vṛtānāṃ dhāvayatāmekadhanamupāhitam bhavatyupavalhāya bibhyatāṃ tānhodīcyānām brāhmaṇānbhīrviveda

Now Uddâlaka Âruni was driving about, as a chosen (offering-priest), amongst the people of the northern country. By him a gold coin was offered; for in the time of our forefathers a prize used to be offered by chosen (priests) when driving about, for the sake of calling out the timid to a disputation. Fear then seized the Brâhmanas of the northern people:--