Moksa Opadesa Yoga: Bhagavad Gita Chapter 18 [Final Revelations of the Ultimate Truth]
Krishna Said > Shaloka: 2
The Supreme Lord said, To give up the results of all activities is called renunciation [tyaga] by the wise. And that state is called the renounced order of life [sannyasa] by great learned men.
The performance of activities for results has to be given up. This is the instruction of Bhagavad-gita. But activities leading to advanced spiritual knowledge are not to be given up. This will be made clear in the next verse. There are many prescriptions of methods for performing sacrifice for some particular purpose in the Vedic literatures. There are certain sacrifices to perform to attain a good son or to attain elevation to the higher planets, but sacrifices prompted by desires should be stopped. However, sacrifice for the purification of one’s heart or for advancement in the spiritual science should not be given up.