Bhagavad Gita

ಯಜ್ಞಾರ್ಥಾತ್ ಕರ್ಮಣೋನ್ಯತ್ರ ಲೋಕೋಯಂ ಕರ್ಮಬಂಧನಃ ।
ತದರ್ಥಂ ಕರ್ಮ ಕೌಂತೇಯ ಮುಕ್ತಸಂಗಃ ಸಮಾಚರ ॥೯॥
yajñārthāt karmaṇonyatra lokoyaṃ karmabaṃdhanaḥ |
tadarthaṃ karma kauṃteya muktasaṃgaḥ samācara ||9||

Gist of the sloka:
One who walks in the direction where the karmas have no reference to Lord, will forever be trapped in the karmic cycle. O Kauntaeya, renounce the rewards of actions and dedicate the actions as worship of the Lord.
The world is trapped into karmic cycle. Even so, all karmas are not binding the souls to karmic cycle. Whatever actions we take, it should be with the awareness of the Lord. We are puppets in his hands. He is the director. With this alertness, if one performs his actions, those actions will not be binding to him and will become, instead our yagna to the Lord.
We breathe in oxygen and breathe out carbon-di-oxide. We are not in aware of how all these happen. What we let out, the plants take it as food and what it lets out, becomes our vital air. All this is the Lord mysterious creation.
In fact, we in India recognize the enormous potential for oxygen generation that peepul tree has and hence worship it and believe the Lord has kept his special potential to this tree. Similarly, if we start seeing the special Lord potential in the objects around us, it itself becomes a way of worship of Lord. Then actions will not become binding or hindrance.
Yagna here means “yaja-deva-pooja” or worship of Lord. One who receives the worship is also called ‘yagna’. The fire sacrifice alone is not yagna but any action which worships the Lord. We are not to change our view about karma but the way we look at those karmas [as related to worship of Lord].
Karma can be split as “ka+ma”. Ka means kara or tax. It is the tax we need to pay to the Lord for being subjects of his kingdom. Lord does not need tax in form of money. He has little use for it. The worship we do to him is the tax which we pay. These could be actions we do to benefit the society at large to individual actions – all being done with Lord in mind. This clears the path to moksha.
Lord addresses Arjuna as ‘Kauntaeya’. There is a specific reason why Lord Krishna addressed Arjun like this. Kunti [Arjuna’s mother] even though born in a big rich family never once had the opportunity to live in the richness and comforts. All her life, she spent in one form of difficulty or another, including majority of time in forest. She was never given her proper place in the kingdom. When finally, the children conquered the kingdom, it was time for her to withdraw to forest for her last days. All along she was the one, filling the children with motivation, reminding them of their duties etc., When Lord Krishna asked what she wanted as a boon, she asked for difficulties in life. For she said it was only then that one remembered the Lord. She wanted to remember the Lord at all times. She is an embodiment of how a person should conduct himself in all difficulties and when happiness occurs.
Lord Krishna is reminding Arjuna, of how his mother conducted herself through her karma yoga. Continuing Lord Krishna gives a small explanation of how one should conduct.