Mbh 12.270.1e

[1266] One whose soul is for Renunciation based upon contentment is regarded as the refuge of true knowledge. Renunciation, in which is that knowledge which leads to Emancipation, and which is highly necessary for a Brahmana, is eternal (and comes down from preceptor to pupil for ever and ever).[1267] Renunciation sometimes exists mixed with the duties of other modes. But whether existing in that state or by itself, one practises it according to the measure of one's strength (that depends upon the degree of one's absence of worldly desires). Renunciation is the cause of supreme benefit unto every kind of person. Only he that is weak, fails to practise it. That pure-hearted man who seeks to attain to Brahma becomes rescued from the world (with its misery).'[1268]