[152] Now at that time the yakkha Vajirapāṇī, holding a great iron hammer, burning, blazing, and glowing, stood in the air above the young man Ambaṭṭha, thinking: "If this young man Ambaṭṭha, when asked a legitimate question by the Blessed One up to the third time, does not answer, I shall split his head into seven pieces right here."
And both the Blessed One and the young man Ambaṭṭha saw that yakkha Vajirapāṇī.
Then the young man Ambaṭṭha, frightened, agitated, with his hair standing on end, sought shelter in the Blessed One alone, sought a haven in the Blessed One alone, sought refuge in the Blessed One alone; and having sat down close by, he said to the Blessed One: "What was it that the worthy Gotama said? May the worthy Gotama please say it again."
"What do you think, Ambaṭṭha? What have you heard from elderly, aged brahmins, teachers of teachers, when they were speaking: from what source did the Kaṇhāyanas originate, and who was the forefather of the Kaṇhāyanas?"
"Worthy Gotama, I have heard it just as the worthy Gotama has said: from that very source did the Kaṇhāyanas originate, and he was the forefather of the Kaṇhāyanas."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.