Bhagavad Gita: Chapter 2, Verse 39

एषा तेऽभिहिता सांख्ये बुद्धिर्योगे त्विमां श‍ृणु ।
बुद्ध्या युक्तो यया पार्थ कर्मबन्धं प्रहास्यसि ॥ २-३९ ॥

eṣā te ’bhihitā sāṅkhye buddhir yoge tv imāṁ śṛṇu
buddhyā yukto yayā pārtha karma-bandhaṁ prahāsyasi 2.39

Thus far I have described this knowledge to you through analytical study (Sankhya Yog). Now listen, as I explain it in terms of working without fruitive results, the Buddhi Yog. O Partha, When you work with such understanding, you will be freed from the bondage of karma.