Bhagavad Gita 18.19
ज्ञानं कर्म च कर्ता च त्रिधैव गुणभेदत: |
प्रोच्यते गुणसङ् ख्यने यथावच्छृणु तान्यपि
Translation
Knowledge, action, and the doer are declared to be of three kinds in the Sānkhya philosophy, distinguished according to the three modes of material nature. Listen, and I will explain their distinctions to you.