सत्सङ्ग

Satsang means the company of the wise, where the Lord and the truth are spoken of. It is the tradition's label, not a word of the Gita. The Gita describes the thing without naming it: those whose minds and lives are given to the Lord enlighten one another, always speak of Him, and are content and rejoice (Gita 10.9).

In that description the explaining goes both ways: there is no fixed teacher and no fixed pupil. The fruit is twofold, contentment and joy. From the learner's side the same thing is said in chapter 4: receive knowledge from those who have seen the truth, with humility, questions and service (Gita 4.34).

Common misreading: that satsang means merely sitting in a gathering or lecture.

Better sense: a life of mutual explaining and talk in which contentment and joy are found.

The whole passage is in Knowing His Glory Leads to Devotion.