A wet log of wood doesn't burn even when lit however many times. It catches fire only when it is dry. Of course, drying of wood itself can be attained by continuous efforts to burn wooden log. However, that is a long process likely to fail and the reason is because lighting the wood is not meant to dry wet wood. To dry a wet wooden log, putting the log out in the sun is the means. Though the goal is to burn wood, the means to dry wet wood is not lighting wood on fire. Similarly, although knowledge alone gives moksha, the means for knowledge to take place is चित्तशुद्धि। That चित्तशुद्धि may come from श्रवण, but it is not a direct means for the same. What indeed is the means for सत्त्वशुद्धि is साधनचातुष्टय। To cut short the same and to assume that श्रवण would result in चित्तशुद्धि is a sure means to disaster. Neither will knowledge arise nor is there likelihood of अन्तःकरण attaining a level of purity needed any time soon. What is understood would only be what is thought to be understood, but not अविद्याविरोध ज्ञान। Bhagavatpadacharya says at multiple places that the rise of knowledge for one bereft of purity of the mind is impossible. Therefore, one should not treat श्रवण as the means to the same, akin to trying to dry wet wood by fire.
ॐ तत् सत्।