Jaiminīya Upaniṣad Brāhmaṇa 3.14

He asks him when he has arrived: 'Who are you?'
If he announces himself by name or by clan [gotra], he says to him: 'This self of yours which was in me, that is yours.'

On that self there is a falling back;
the seasons drag him down, seized by his feet together;
day and night obtain his world.

To him he should declare with this: 'Who am I? You are heaven.
Such as I am, I have come to you, the heavenly light [svar].'

Who [Ka] indeed is Prajāpati; and one who knows thus is heavenly;
for he goes to heaven.

He says to him: 'Who you are, that am I; who I am, that are you. Come!'

He enters this very essence of good deeds.
Whatever human beings sacrifice in this world, whatever good they do, their food-essence rises upward;
it enters that moon, the world of human beings.

This human-resembling egg forms within the belly;
its food-essence rises upward toward the breasts;
when he is born, then the mother offers him the breast, the food-essence.

A man is indeed unborn as long as he does not sacrifice;
he is born only through the sacrifice;
just like an egg broken open for the first time, even so is it.

Then indeed the udgātṛ who knows thus makes that sacrificer reach the sun, the world of the gods, by this syllable om;
by the subsequent syllable 'vāc' he bestows upon him the moon, food-essence, imperishability.

Now for whomsoever an unknowing one sings the udgītha, he neither makes him reach the world of the gods nor does he enrich him with food-essence.

Just as an egg smeared [with dirt/filth] would lie without obtaining food-essence, even so he lies smeared, without obtaining food-essence.

Therefore one should have only one who knows thus sing the udgītha.
Called with 'O udgātṛ who knows thus here!', he should respond.
Fifth khaṇḍa in the third anuvāka.
The third anuvāka is concluded.