1. To address the Prophet (peace be upon him) with these words and then to command him to rise and keep standing in the Prayer at night, shows that at the time he either lay asleep, or had wrapped himself up in a sheet in order to go to sleep.
Here, to address him with: O you who sleeps wrapped up instead of with: O Prophet, or O Messenger, is a fine way of address, which by itself gives the meaning:
Gone is the time when you used to enjoy peaceful sleep at will; now you lie under the burden of a great mission, whose demands and duties are different as well as onerous.
(73:2) Stand up in Prayer by night, all but a small part of it;2
2. This can have two meanings:
(1) Pass the night standing up in the Prayer and spend only a little of it in sleep.
(2) There is no demand from you to pass the whole night in the Prayer, but have rest as well and spend a little part of the night in worship too.
But in view of the theme that follows the first meaning seems to be more relevant, and the same is supported by (Surah Ad-Dahr, Ayat 26), in which it has been said: Prostrate yourself before Him in the night and glorify Him during the long hours of night.
