Mbh 5.42.2a

“Sanat-sujata said, ‘Some say, death is avertable by particular acts; in others’ opinion there is no death; thou hast asked me which of these is true. Listen to me, O king, as I discourse to thee on this, so that thy doubts may be removed. Know, O Kshatriya, that both of these are true. The learned are of opinion that death results from ignorance. I say that ignorance is Death, and so the absence of ignorance (Knowledge) is immortality. It is from ignorance that the Asuras became subject to defeat and death, and it is from the absence of ignorance that the gods have attained the nature of Brahman. Death doth not devour creatures like a tiger; its form itself is unascertainable. Besides this, some imagine Yama to be Death. This, however, is due to the weakness of the mind. The pursuit of Brahman or self-knowledge is immortality. That (imaginary) god (Yama) holdeth his sway in the region of the Pitris, being the source of bliss to the virtuous and of woe to the sinful. It is at his command that death in the form of wrath, ignorance, and covetousness, occurreth among men. Swayed by pride, men always walk in unrighteous path. None amongst them succeeds in attaining to his real nature. With their understanding clouded, and themselves swayed by their passions, they cast off their bodies and repeatedly fall into hell. They are always followed by their senses. It is for this that ignorance receives the name of death. Those men that desire the fruits of action when the time cometh for enjoying those fruits, proceed to heaven, casting off their bodies. Hence they cannot avoid death. Embodied creatures, from inability to attain the knowledge of Brahman and from their connection with earthly enjoyments, are obliged to sojourn in a cycle of re-births, up and down and around. The natural inclination of man towards pursuits that are unreal is alone the cause of the senses being led to error.