Chapter 4 · Knowledge and Renunciation of Action · Krishna said
Bhagavad Gita 4.3 — Told to a devotee and friend
स एवायं मया तेऽद्य योगः प्रोक्तः पुरातनः। भक्तोऽसि मे सखा चेति रहस्यं ह्येतदुत्तमम् ॥
sa evāyaṃ mayā te'dya yogaḥ proktaḥ purātanaḥ | bhakto'si me sakhā ceti rahasyaṃ hyetaduttamam ||
Meaning
That same ancient yoga I have told you today, because you are my devotee and my friend. It is a supreme secret.