The least altruistic action that we have done gives lasting peace of mind. Work for the happiness of others leaves me with lasting satisfaction as time goes by. The deepest moments of meditation, profound meditation, will give lasting satisfaction. If if we have had any intuition of our real nature, that all, of course, ultimately, that's the greatest thing.
Swami Sarvapriyananda teaches Chapter 6 (Verses 36-42) of the Bhagavad Gita. In this series of talks, Swami Sarvapriyananda unfolds the highest truths of Vedanta through the study of the Bhagavad Gita (The Song of God).