Bhagavad Gita 2.47 · Karmanye Vadhikarasteकर्मण्येवाधिकारस्ते मा फलेषु कदाचन।मा कर्मफलहेतुर्भूर्मा ते सङ्गोऽस्त्वकर्मणि ॥

When you perform actions have no desire for the fruits thereof under any circumstances. If you thirst for the fruits of your actions, you will have to take birth again and again to enjoy them. Action done with expectation of fruits (rewards) brings bondage. If you do not thirst for them, you get purification of heart and you will get knowledge of the Self through purity of heart and through the knowledge of the Self you will be freed from the round of births and deaths.Neither let thy attachment be towards inaction thinking what is the use of doing actions when I cannot get any reward for themIn a broad sense Karma means action. It also means duty which one has to perform according to his caste or station of life. According to the followers of the Karma Kanda of the Vedas (the Mimamsakas) Karma means the rituals and sacrifices prescribed in the Vedas. It has a deep meaning also. It signifies the destiny or the storehouse of tendencies of a man which give rise to his future birth.