Chapter 4 · verse 3 · gita.yoga.org

Bhagavad Gita 4.3

स एवायं मया तेऽद्य योगः प्रोक्तः पुरातनः। भक्तोऽसि मे सखा चेति रहस्यं ह्येतदुत्तमम्

That same ancient yoga has been today taught to you by me, for you are my devotee and my friend; it is the supreme secret.