(Extract Q&A session at the 1998 International Vo-Vi Convention in Alaska  - DVD 2)
Question:
While practicing the mental invocation of Nam-Mo-A-Di-Da-Phat, there are some who feel at times relaxed and at times agitated, even though they have curled their tongue up, incisors against incisors, and focus on the top of their head. But it still does not help. Is it caused by the circulation of spiritual energy in our body, or by the release of impure energy?

Answer:

When your flux of central energy cannot yet communicate with the flux of central energy of the universe, you will feel at times heavy and at times light. If you devote yourselves assiduously to the constant practice of the mental invocation of Nam-Mo-A-Di-Da-Phat, you will eventually communicate with the flux of central energy of the universe. At that time, whenever we think of Nam-Mo-A-Di-Da-Phat, we will feel pure and light. This is called "Serenity". When you arrive to that state, this is the serene state. When you are able to project your energy upward, you have attained serenity.