स एवायं मया तेऽद्य योगः प्रोक्तः पुरातनः | भक्तोऽसि मे सखा चेति रहस्यं ह्येतदुत्तमम् ||
Sa evayam maya te adya
I am teaching you this ancient knowledge because you are my devotee and friend.
Modern Application: Trust is required for deep knowledge.
Deep Wisdom: Krishna reveals that spiritual wisdom is given to those who are sincere and devoted.