Even the best of meditation, in the initial stages, it's difficult to attain calmness of mind. One may attain deep samadhi and then one can stay in that for a long period of time. But beyond that, it still goes away. Another insight he says, nachayams, titas chalati, taktotah. Very interesting. He says, once attaining to this, one can never lose it again.
Swami Sarvapriyananda teaches Chapter 6 (Verses 24-25) 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).