Bhagavad Gita · Chapter 4: Knowledge and the Renouncing of Action
Bhagavad Gita 4.16
किं कर्म किमकर्मेति कवयोऽप्यत्र मोहिताः ।
तत्ते कर्म प्रवक्ष्यामि यज्ज्ञात्वा मोक्ष्यसेऽशुभात् ॥
kiṃ karma kimakarmeti kavayo'pyatra mohitāḥ | tatte karma pravakṣyāmi yajjñātvā mokṣyase'śubhāt ||
What is action? What is inaction? Even the wise are confused about this. I will explain action to you, and knowing it you will be freed from harm.
Modern context
The question sounds simple and is not. Is sitting still inaction? Is being busy action? Krishna admits that even the wise get confused here. That admission is reassuring. Uncertainty about how to act rightly is no sign of stupidity. It is a difficulty built into the subject, and it deserves careful thought.