नियतस्य तु संन्यासः कर्मणो नोपपद्यते।
मोहात्तस्य परित्यागस्तामसः परिकीर्तितः।।18.7।।
।।18.7।। नियत कर्म का त्याग उचित नहीं है मोहवश उसका त्याग करना तामस त्याग कहा गया है।।
Prescribed Vedic activities are niyata or eternal. Some are daily duties such as chanting mantras or sacred incantations for the benefit of all creation at the three junctures of the day. Some are occasional duties such as fasting from all grains twice a month on ekadasi which is the 11th day of the waxing and waning moon. Still other prescribed Vedic activities such as a Vishnu yagna which is ritualistic propitiation and worship of the Supreme Lord are performed during extraordinary celebrations such as the installation of the vigraha or authorised deity form of the Supreme Lord Krishna or any of His authorised incarnations and expansions as revealed in Vedic scriptures. Ceasing to performed such sanctifying and purifying Vedic activities which benefit all creation would be unrighteous and cause unimaginable degradation to humanity specifically and evolution in general. Lord Krishna already confirmed in chapter three, verse 8: That bodily sustenance cannot even be maintained without appropriate actions otherwise it is not possible. . Even if one is able to assimilate bodily sustenance from sunshine or by air alone as some elevated yogis do that is still performing action. Food not first consecrated unto the Supreme Lord is considered sinful and such food produces delusion and bewilderment in thinking. It is confirmed in Chandogya Upanisad VI.V.IV beginning anna mayam hi somya mana states: The mind is verily composed from food. The purifying vestiges of sanctified food ingested after the performance of the holy yagna is capable of imparting sacred knowledge conducive to atma tattva or soul realisation. Cognition of the Supreme Lord and communion with Him is dependent upon internal and external purity which are mandatory pre-requisites. Purified food purifies the mind, a purified mind has the ability to access the esoteric spiritual reality that assures moksa or liberation from material existence. So the reality is that prescribed Vedic activities and obligatory duties are to be performed all throughout ones life even up to the last day of departing the present existence as they guarantee one is able to fulfil the goals of human existence. So abstinence from performing them is not in ones best interest. Those that desist, ignore, disregard and blaspheme are influenced by illusion and are locked in tama guna the mode of ignorance. For it has been traced by the enlightened that the idea of abstinence of prescribed Vedic activities was induced by tama guna and governed by illusion. Ignorance is that which is hostile to wisdom and exists as perverted knowledge. So abstaining from prescribed Vedic activities is in the category of perverted knowledge. Lord Krishna will illustrate this futher in verse 32.