Mahabharata Santi Parva Chapter 250:2

Mahabharata Santi Parva (Mokshadharma Parva) Chapter 250:2 Crossing it, thou wilt succeed in freeing thyself from every attachment, acquiring a tranquil heart, knowing the Soul, and becoming pure in every respect. Relying then on a purged and elevated understanding, thou wilt succeed in becoming Brahma's self. Having dissociated thyself from every worldly attachment, having acquired a purified Soul and transcending every kind of sin, look thou upon the world like a person looking from the mountain top upon creatures creeping below on the earth's surface. Without giving way to wrath or joy, and without forming any cruel wish, thou wilt succeed in beholding the origin and the destruction of all created objects. They that are endued with wisdom regard such an act to be the foremost of all things. Indeed, this act of crossing the river of life is regarded by the foremost of righteous persons, by ascetics conversant with the truth, to be the highest of all acts that one can accomplish. This knowledge of the all-pervading Soul is intended to be imparted to one's son. It should be inculcated unto one that is of restrained senses, that is honest in behaviour, and that is docile or submissive. This knowledge of the Soul, of which I have just now spoken to thee, O child, and the evidence of whose truth is furnished by the Soul itself, is a mystery,—indeed, the greatest of all mysteries, and the very highest knowledge that one can attain. Brahma hath no sex,—male, female, or neuter. It is neither sorrow nor happiness. It hath for its essence the past, the future, and the present. Whatever one's sex, male or female, the person that attains to the knowledge of Brahma hath never to undergo rebirth. This duty (of Yoga) hath been inculcated for attaining to exemption from rebirth. These words that I have used for answering thy question lead to Emancipation in the same way as the diverse other opinions advanced by diverse other sages that have treated of this subject. I have expounded the topic to thee after the manner in which it should be expounded. Those opinions sometimes become productive of fruit and sometimes not. (The words, however, that I have used are of a different kind, for these are sure to lead to success). For this reason, O good child, a preceptor, when asked by a contented, meritorious, and self-restrained son or disciple, should, with a delighted heart, inculcate, according to their true import, these instructions that I have inculcated for the benefit of thee, my son!'