(It is Allah Who takes away the souls at the time of their death, and those that die not during their sleep. He keeps those (souls) for which He has ordained death and sends the rest for a term appointed.)39:42, ,thus mentioning both minor and major death. Allah says,
In the third verse, this subject has been further enlarged by saying that Allah Ta` ala has absolute subduing power over all His servants. As long as He wills to have them living, He assigns angels to protect them as a result of which no one dares harm them. And when one has reached the appointed limit of one's age, these very guardian angels become the agents of one's death without ever falling short in providing the relevant causes leading to one's death. Then, death is not all, for the matter is still not closed. Instead of that, there is the next phase, that of: رُدُّوا إِلَى اللَّـهِ ; (Then they are returned to Allah - 62). It means that they will be made to rise again and be presented before Allah Ta` ala. If, at this point, one were to think of having to appear before the greatest Judge of judges and stand before Him to account for a whole life-time of deeds, one cannot even dare to imagine to come out unscathed and hope to escape punishment. Therefore, along with it, it was said: إِلَى اللَّـهِ مَوْلَاهُمُ الْحَقِّ to Allah, their real Master - 62). It means that Allah Ta` ala is not only the Sovereign and the Judge of judges, He is also the Master and Guardian of His servants who reaches out to help them at all times of their need.
Our earth is a unique phenomenon in the whole universe. The system prevailing here has been made congenial to the conditions of God’s creatures—human beings. A major part of the interior of the earth consists of fire but it does not burst open. The sun is at exactly the right distance mathematically, and does not move closer or farther away. A man always needs air and water; so air has been spread over the earth in gaseous form and water has been stored under the surface of the earth in liquid form. There are countless similar arrangements that are constantly maintained in the right proportions on the earth. If there were even a slight variation in these, it would be impossible for a human being to live here. Sleep is a wonderful thing. Man roams about here and there; he sees and speaks; but when he sleeps all his senses become suspended, just as if life had oozed out of them. When he has had his full sleep and wakes up, he becomes as active as before. This is, so to say, an example of life and death. This event demonstrates how a man will die and how he will be resurrected, i.e. be brought back to life. These events prove that all men are in the power of God and soon that Day will come when God will take fateful decisions about them in the exercise of His powers.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.