Shrimad Bhagavad Gita As It Is -Shri Shrimad A.C Bhaktivedanta Swami Prabhupada
Conclusion—The Perfection of Renunciation
Chapter 18: Verse- 2
sri-bhagavän uväca kämyänäm karmanäm
The Supreme Personality of Godhead said: The giving up of activities that are based on material desire is what great learned men call the renounced order of lifeAnd giving up the results of all activities is what the wise call renunciation 
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 verses. In the Vedic literature there are many prescriptions of methods for performing sacrifice for some particular purpose. 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.
- sri-bhagavän uväca=the Supreme Personality of Godhead said; kämyänäm=with desire; karmanäm=of activities; nyäsam=renunciation; sannyäsam=the renounced order of life; kavayah=the learned; viduh=know; sarva=of all; karma=activities; phala=of results; tyägam=renunciation; prähuh=call; tyägam=renunciation; vicaksanäh=the experienced.