As the Brihadaranyaka Upanishad tells it
Brihadaranyaka Upanishad 5.2 · 2 min read
Prajapati had three kinds of children: the gods, the humans and the Asuras. The Upanishad says that all three lived with their father as students.
A student in the Upanishads lives with his teacher until the learning is complete, and only then asks leave to go. So the gods, the humans and the Asuras, who quarrel with one another in so many other stories, all sat under the same teacher, and he was their father.
When their time as students was over, the gods came to him first.
"Tell us something, sir," they said.
Prajapati answered with one sound.
"Da."
Then he looked at them. "Did you understand?"
"We understood," said the gods. "You told us damyata. Restrain yourselves."
"Yes," said Prajapati. "You have understood."
The gods left. Then the humans came and stood where the gods had stood.
"Tell us something, sir," they said.
He gave them the same sound.
"Da."
"Did you understand?"
"We understood," said the humans. "You told us datta. Give."
"Yes," said Prajapati. "You have understood."
The humans left. Last of all came the Asuras, the rivals of the gods.
"Tell us something, sir."
"Da."
"Did you understand?"
"We understood," said the Asuras. "You told us dayadhvam. Be merciful."
"Yes," said their father. "You have understood."
That is all that happens. The Upanishad names no place and no season, and it does not say how long the three had studied. It gives only the request, the syllable and the answer, three times over. The teacher said one syllable three times. He never said which word he meant. Each group of his children finished the word for itself, and each time he told them they were right.
You might ask why the gods heard restraint in it, the humans heard giving, and the Asuras heard mercy. The Upanishad does not explain. Each of them hears a word that begins with that sound, and the father agrees with all three.
Then it adds one thing more, and this is the part people remember.
The lesson, it says, was not given only once. The voice of the sky repeats it. When the thunder rolls, it is saying what Prajapati said.
"Da. Da. Da."
Restrain yourselves. Give. Be merciful.
So, the Upanishad ends, these three should be taught: self-control, giving and mercy. It does not say that the first is only for gods, the second only for humans and the third only for Asuras. It names all three together, for anyone who hears the thunder.