Śatapatha Brāhmaṇa ("of a hundred paths") 11.2.1

Verily, man is born thrice, namely in this way:--first he is born from his mother and father; and when he to whom the sacrifice inclines performs offering he is born a second time; and when he dies, and they place him on the fire, and when he thereupon comes into existence again, he is born a third time;--wherefore they say, 'Man is born thrice.'

He (the Hotri) recites those eleven kindling-verses,--there are these ten vital airs in man, and the body in which these vital airs are established is the eleventh,--so great, indeed, is man: he thus causes him to be born complete. And what comes after the kindling-verses that is the foundation: thus, having caused him to be born, he establishes him.

There are nine utterances of impulsion (or quickening),--there are these nine vital airs in man: he thereby causes him to be born a second time; and the (Adhvaryu's) call and (the Âgnîdhra's) response are the foundation. And when there, on the occasion of the throwing (of the grass-bunch into the fire), birth is spoken of, he thereby causes him to be born a third time: on this occasion the Patnîsamyâgas are the foundation.

For thrice, indeed, man is born, and it is just in this way that he causes him to be born thrice from the sacrifice. Of those eleven (kindling-verses) he recites thrice the first and last:--

This makes fifteen kindling-verses,--there are two libations of ghee (âghâra), five fore-offerings, the Idâ, three after-offerings, the Sûktavâka, and Samyorvâka --that makes thirteen oblations. And when there, at the Patnîsamyâgas, he takes up at the same time (the two spoons); and the Samishtayagus:--

That makes fifteen oblations:--for these fifteen oblations those fifteen kindling-verses (serve, as it were, as) invitatory formulas; and for these invitatory formulas these (serve as) offering-formulas--whatever formula (is used) there (at those oblations) and what Nigada (is used at the invocation of the Idâ) that is of the form of offering-formulas. Thereby, then, those oblations of his come to be supplied with invitatory formulas through those kindling-verses; and through those oblations those invitatory formulas come to be supplied with both offering-formulas and oblations.