Aitareyabrahmana 3.33

3.33

Prajāpati desired his own daughter:
'The sky,' some say; 'Dawn,' say others.
Becoming a stag, he approached her who had become a female deer.
The gods saw him: 'Prajāpati is doing what has not been done.'
They sought him who should pierce him, but they did not find him among one another.
Those forms of theirs which were the most terrible they brought together into one.
Brought together, they became this god; therefore this is his name containing 'bhūta' [Bhūtavat/Rudra].
He thrives [bhavati] who knows this name of his thus.
The gods said to him:
'This Prajāpati has done what has not been done; pierce him.'
He said, 'So be it; let me choose a boon from you.'—'Choose,' [they said].
He chose just this boon: lordship over cattle.
Therefore this is his name containing 'cattle' [Paśumat/Paśupati].
He becomes possessed of cattle who knows this name of his thus.
Aiming at him, he pierced him. Pierced, he flew upwards;
they call him this 'Deer' [Mṛga/Orion].
And he who is the deer-slayer [Mṛgavyādha/Sirius] is indeed he; she who was the female deer is Rohiṇī [Aldebaran];
and the arrow that has three joints is indeed that three-jointed arrow [Belt of Orion].
Now this semen of Prajāpati was poured out and ran forth; it became a lake.
The gods said, 'Let not this semen of Prajāpati be spoiled [mā duṣat]!'
Because they said, 'Let not this semen of Prajāpati be spoiled,' it became māduṣa;
that is the māduṣa-nature of māduṣa.
Māduṣa is indeed the name for what is mānuṣa [human];
being māduṣa, they call it cryptically mānuṣa,
for the gods love the cryptic, as it were.