Spoken by Supreme Master Ching Hai,
Seven-day retreat, Hsihu, Formosa February 13-18, 1989
(Originally in Chinese) MP3-4
What should we do if we want to meditate a lot and not feel tired? The secrets are: Talk less, don't look around, don't think of others' goodness or badness and just recite the Holy Names 24 hours a day. If you feel unstable in doing the Sound meditation, then recite the Holy Names for several minutes before doing the Sound meditation again. Should you feel any part of your body ache or become numb, just take no heed of it ! When you are in samadhi later, you don't sense that the whole body exists. Therefore, don't scratch around. When you get tired of doing Sound meditation, change your posture and do Light meditation. Your legs will then be very grateful to you for that. For they ache a lot and the head is taut from the previous posture. If you change your posture and do Light meditation at this moment, it will feel much better. So you should do the Light and Sound meditations alternately, and they will be helpful to each other and you can meditate longer without tiredness.
Some of our fellow practitioners can meditate for the whole night. It is because they do the Light and Sound meditations alternately. But don't do that too frequently and change your posture in five minutes, for this is useless. For the longer time you remain in the same posture, the better. The Light and Sound meditations are helpful to each other. When having sat for too long in Light meditation, and sometimes you feel tired and achy, you can change your posture and do the Sound meditation in this way. You will then feel much better, for there is seemingly something to rely on. This secret in practicing meditation is quite unknown to many.