Sage Ushasti learnt that the king was performing a yaga and
went to meet him because he knew a priest would be needed
to perform the yaga. But by the time he arrived, the yaga had
already commenced and there were already three priests
there. Three priests are necessary for performance of the
yaga: prastota — initiator, udgata — chanter and pratiharta
—concluder.Ushasti asked the priests if they knew to which deity they were chanting their respective mantras, said M.K. Srinivasan in a discourse.
If they chanted the mantra without knowing this, their
heads would fall of, warned Ushasti. The rule is that if a
vidwan is present and the priests chant without knowing the
name of the deities, then their heads will fall of. So now the
three priests could not chant the mantras, because Ushasti, a
vidwan, was present. The king asked Ushasti who he was and the sage introduced himself. The king said that he had in fact been looking for Ushasti to conduct the yaga, but had been unable to locate him. That is why he had started his yaga with the other three priests. He then requested Ushasti to perform the yaga. But Ushasti declined the ofer. He said:
“Let them perform what they have started. I will inform them
about the deities they are addressing.”
The prastota requested Ushasti to instruct him. Ushasti
said that the deity to whom his mantras were addressed was
Prana. Ushasti told the Udgata that the mantras he chanted
were addressed to Aditya. He told the pratiharta that the
deity he was addressing was food (anna). All these deities
are pervaded by Paramatma.
Though he taught the three priests, Ushasti generously
accepted the same fee that was paid to them.