Mbh 12.335.4a

"'"The holy one said, 'This topic is one about which nothing should be said. It is an ancient mystery. Thy devotion to me is very great. Hence, O regenerate one, I shall discourse to thee on it agreeably to the truth. That which is minute, which is inconceivable, unmanifest, immobile, durable, destitute of all connection with the senses and the objects of the senses, that which is dissociated from the (five) elements--that is called the in-dwelling Soul of all existent creatures. That is known by the name of Kshetrajna. Transcending the three attributes of Sattwa, Rajas, and Tamas, that is regarded as Purusha in the scriptures. From Him hath followed the unmanifest, O foremost of regenerate ones, possessed of the three attributes of Sattwa, Rajas, and Tamas. Though really unmanifest, she is called indestructible Prakriti and dwell in all manifest forms. Know that She is the source whence we two have sprung. That all-pervading Soul, which is made up of all existent and non-existent things, is adored by us. Even He is what we worship in all those rites that we perform in honour of the deities and the Pitris. There is no higher deity or Pitri than He. O regenerate one, He should be known as our Soul. It is him that we worship. This course of duties followed by men has, O regenerate one, been promulgated by Him. It is His ordinance that we should duly perform all the rites laid down in respect of the deities and the Pitris. Brahman, Sthanu, Manu, Daksha, Bhrigu, Dharma, Yama, Marichi, Angiras, Atri, Pulastya, Pulaha, Kratu, Vasishtha, Parameshthi, Vivaswat, Shoma, he that has been called Karddama, Krodha, Avak, and Krita,--these one and twenty persons, called Prajapatis, were first born. All of them obeyed the eternal law of the Supreme God. Observing all the rites, in detail, that were ordained in honour of the deities and the Pitris, all those foremost of regenerate persons acquired all those objects which they sought.