It’s a big deal in Theravadan circles to not get too much sleep. Sometimes it is a encouraging sort of thing to “Get up and meditate! Don’t waste the time you have, especially on retreat!” Other times it’s more of a macho sort of thing that strikes me a veering off the middle way. Where does it come from?
Well, at least in part it comes from the suttas. Sleepiness (not just sloth) is one of the hindrances to meditation. It is also one of the 10 Lower Fetters. The Buddha gives a number of tools to try to overcome sleepiness before giving in and taking a nap. According to the Sekha sutta, delight in sleeping is one of the 5 things that leads to “the decline of a monk.” Here’s a lovely passage about these lazy monks:
For now monks leave diligent and work hard for liberation. They use a block of wood for a pillow. Mara the Evit One can’t interfere with their spiritual practice. But in the future monks with soft, beautiful hands and feet will sleep until sunrise and get very fat.
-Samyutta Nikaya, Opammasamyutta (19), Sutta 8
What was the Buddha’s sleeping routine like? Well, for one thing, he slept fairly little at night. According to the commentaries in the evening he would give teachings to the monks. Around midnight he would give teachings to angels (devas). He would then to a little walking, sleep for a a couple of hours or so, and then wake and sit until sunrise. But balance that with the idea that he often took an afternoon nap. In a couple of suttas he was chided by Mara for resting. He responded with, “My work is done. I can rest in calm.” (S 4.7/1:107 Supati Sutta) This idea of sleeping in two chunks is sometimes called biphasic sleeping, and it is common in some warm-weather countries. It is basically the idea of the siesta. It makes sense in places that are blazing hot in mid-day. Other suttas have him walking for more of the night. Any way you slice, it this is very little sleep.
Is it really possible to sleep so little? The answer is certainly yes. Maybe people on meditation retreats sleep very little, even for long periods of time. I think most people serious meditation retreat notice that the need for sleep declines. Maybe meditation itself fulfills part of the function of sleep.
In all honesty, I have not found for myself dramatically little sleep to be helpful for meditation. Quite the contrary. On the other hand, over-sleeping is even worse.
I myself went on very little sleep for about 9 months at one point. I was doing polyphasic sleeping. For the first couple of monks I slept only 2 hours a day, taking a 20-minute every 4 hours. For the remaining 7 months I slept 4 hours a day. 3 Hours at night with 3 20-minute naps. I was perfectly fine. My health was good, and after I got used to I wasn’t sleepy at all. In fact, I was less sleepy than I had been before. But for all that my meditation suffered. I wouldn’t recommend it. After that period I was much more disciplined about getting “ordinary” sleep, and my meditation improved.
Culturally, I imagine that it was very important for monks who lived on the generosity of hard-working farmers not to be seen lolling around, sleeping in while the peasants toiled.
Other interesting info about sleep
On Uposatha days (approximately once a week), the Buddha encourages his lay follows to take on an extra 3 precepts. The basic 5 are of course no killing, stealing, lying, having affairs, or drinking alcohol. Once a week the Buddha adds to that: don’t eat after noon, don’t wear garlands or perfume, and sleep at floor level. Tricky for apartment dwellers!
Over and over the suttas teach that the best cure for sleeping problems (can’t get to sleep, nightmares, etc.) is…metta meditation.