Bhagavad Gita



ಏವಂ ಪ್ರವರ್ತಿತಂ ಚಕ್ರಂ ನಾನುವರ್ತಯತೀಹ ಯಃ।
ಅಘಾಯುರಿಂದ್ರ ಯಾರಾಮೋ ಮೋಘಂ ಪಾರ್ಥ ಸ ಜೀವತಿ ॥೧೬॥
evaṃ pravartitaṃ cakraṃ nānuvartayatīha yaḥ|
aghāyuriṃdra yārāmo moghaṃ pārtha sa jīvati ||16||

Gist of the sloka:
While the cycle of the time continues, one who is forever swimming in the sinful state, enjoying the sensual aspects and forgetting himself, O Partha, his life is wasted.
Explanation:
Like explained in the earlier verse 3:11; the cycle goes on as follows.
Mankind - food - rains - yagna - Lord - Veda's - mankind
All karmas need to be done with dedication, sincerity and with the belief it’s the Lord who is making it happen and we offer it as a form of worship to the Lord himself. This is what the Veda's also purport. If there is action without Lord in it, then it is not considered viable karma at all. Lord resides in the Veda's and to such a Lord the karmas need to be offered. This is karma yoga.
Knowing the Veda does not mean just knowing the words. It means knowing the meaning of each letter, for each of them gives out the quality of the Lord. With such Vedic mantras and with the awareness that it represents and denotes qualities of the Lord, if an yagna is conducted, then such worship is accepted by the Lord. When such worship happens, Lord provides for food to the mankind, who otherwise cannot survive.
This is the universal cyclic progress. If anyone stops from participating or prevents the cycle from continuing, then such a person has committed a grave crime against the Lord and would be trapped in the karmic cycle of birth/death for ever.
If we retain the universal cyclic knowledge in our day to day life, our life would be satisfactory. We should also remember the universal force, so that our progress continues. We need not fear anything, and our entire activities would be like worship/yagna.
We should train our minds to think and be conscious of this universal cycle. This will be real karma yoga. This would lead us to moksha and Lord.
The entire universe is interconnected and inter dependent. No one is independent of other. Even in minor action, the forces of the universe are in play. Even behind the food we have, we can see multitude of forces at play. Remembering this aspect, is like paying respect to the universal force/Lord.
Lord Krishna has clearly given us the view, about our duties in the universal cycle, yagna and karma yoga. A question now might arise as to which one of the path is sacred and should be followed. He said earlier that gyana/knowledge path was sacred. Whereas Lord Krishna also told that one cannot get away from karmas. Lord Krishna takes up this very question in the next verse and clarifies.
Scriptures says one who has achieved the highest gynana need not do karma. If one does yagna in his mind, is it karma? If he does not do karma is it a lapse? Which state allows a person not to have attachment to the karmas? Before attaining moksha, does one need to do karma in his householder life? Can one do everything internally? Etc., is answered by Lord.