Chapter 4 · Knowledge and Renunciation of Action · Krishna said
Bhagavad Gita 4.37 — The fire of knowledge
यथैधांसि समिद्धोऽग्निर्भस्मसात्कुरुतेऽर्जुन। ज्ञानाग्निः सर्वकर्माणि भस्मसात्कुरुते तथा ॥
yathaidhāṃsi samiddho'gnirbhasmasātkurute'rjuna | jñānāgniḥ sarvakarmāṇi bhasmasātkurute tathā ||
Meaning
Just as a blazing fire turns wood to ash, Arjuna, the fire of knowledge turns all actions to ash.