Prophet Muhammad (peace be upon him) once asked a companion: "(Is it true)
that you fast all day and stand in prayer all night? The companion replied
that the report was indeed true. The Prophet then said: "Do not do that!
Observe the fast sometimes and also leave (it) at other times; stand up for
prayer at night and also sleep at night. Your body has a right over you, your
eyes have a right over you and your wife has a right over you." Bukhari,