Bhagavad Gita Chapter 3 Sloka 4 (3.4)

ನಚ ಸಂನ್ಯಸನಾದೇವ ಸಿದ್ಧಿಂ ಸಮಧಿಗಚ್ಛತಿ॥೪॥
na karmaṇāmanāraṃbhānnaiṣkarmyaṃ puruṣośnute |
naca saṃnyasanādeva siddhiṃ samadhigacchati||4||
Gist of the sloka:
One who avoids karmas will not get released from duties of karma. One who just renunciates the result of the karmas will not obtain mukthi either.
Explanation:
Scriptures indicate that karma path results in attachment and knowledge path results in release. Whereas, Lord Krishna says, both the paths are needed. Lord giving explanation, tells us that moksha is obtained by performing renunciation of karmic results.
If karma is leading to attachment, then how can one with this gross body remain idle? With the gross body, action is inevitable. Just because one stopped performing actions, moksha does not happen immediately. Actually, one cannot avoid karmas. Action without knowledge becomes mere, mechanical action. Action with knowledge will never lead to attachment. Just because one renounced the results of the action, no immediate benefit is seen. Without any action, one can never see any release from the cycle of birth/death.
Action is required and inevitable, but such action need to be with right knowledge.