Waking up from sleep is by Allah's blessing

As revealed in the Qur’an, every soul shall taste death. Death will come at a totally unexpected time. The time of every individual’s death -- the year, month, day, hour and second -- is ordained in the Sight of our Almighty Lord. There is no way of bringing it forward or postponing it when it comes. Allah will take back our selves in the manner He wills, using a natural cause such as sickness for some people, a traffic accident for others, or old age or something else. And if He so wills, death can come in our sleep.

People generally treat the subject of sleep with great familiarity. They are quite certain they will wake up and get out of bed the next morning. Before going to sleep they make plans for the following day and think about what they will wear, how they will go to wherever, who they will meet and what they will do. A day filled with shopping, meetings, going to work or visiting the doctor is right in their minds. They plan the day in the certainty they will wake up into it. But one can still die in one’s sleep in the expectation of an important event. One may survive diseases and operations and live through traffic accidents but still come face to face with death while one is asleep, when one expects it least. In the Qur’an our Almighty Lord reveals:

It is He Who takes you back to Himself at night, while knowing the things you perpetrate by day, and then wakes you up again, so that a specified term may be fulfilled. Then you will return to Him. Then He will inform you about what you did. (Surat al-An‘am, 60)

 
Our Lord reveals in this verse that sleep is a kind of “death.” Allah puts us to death in sleep and wakes us up again when He so chooses. But when we go to sleep there is no guarantee that we will wake up again. Some people are destined to die in their sleep. Allah takes the souls of those whom He wishes when they are asleep, while He permits others to wake up again at a specific time:

Allah takes back people’s selves when their death arrives and those who have not yet died, while they are asleep. He keeps hold of those whose death has been decreed and sends the others back for a specified term. There are certainly signs in that for people who reflect. (Surat az-Zumar, 42)

 
We wake up from sleep by the will of Allah. One sets one’s alarm clock to wake up at a given time. One imagines one will wake up when one hears it ring. But the fact is that it is our Almighty Lord alone, the Lord of all, Who causes the clock to ring, Who allows us to hear it, Who restores our souls to us and to Whom all thanks are due.