To work during day time and rest at night is based on great Wisdom

And He is the One who has made the night an apparel for you, and the sleep a means of rest and has made the day a means of revival. [ 47]

وَهُوَ الَّذِي جَعَلَ لَكُمُ اللَّيْلَ لِبَاسًا وَالنَّوْمَ سُبَاتًا وَجَعَلَ النَّهَارَ‌ نُشُورً‌ا

The night is referred as the apparel in this verse to describe that it covers up everything like a natural sheet as does the dress to human body. The word سُبَاتًا (subata) is derived from سَبت (sabt) which means to cut out. سُبَات is that thing which cuts out some other thing.

Allah Ta’ ala has made the sleep to shed away the exhaustion and fatigue one develops after the daylong work. In sleep one is cut off with stress and strain of mind and body while they are rested. Hence the word سُبات is generally translated as rest, relaxation or tranquility. So the sense of the verse is that Allah Ta’ ala has created the night as a covering to everything then imposed sleep on men and all living things, so that they rest and relax.

Here one needs to ponder over a few things. Everyone knows that sleep is a blessing and a source of relaxation. But it is human nature to sleep in darkness. It is very difficult to sleep in day light, and even if one goes off to sleep, one is awakened quickly. Conforming to human needs and nature Allah Ta’ ala has made nights dark and cool, so that people can sleep and relax. Hence, night by itself is a blessing and sleep is another blessing. The third blessing is that the entire humanity and animals sleep at night instinctively. If the sleeping time of different people were different from one another, it would have created a number of problems. In such a situation some would have slept at one time and the others at some other, creating problems for one another, because when people are awake, they move about for various works and this movement; would have created noise to the annoyance and disturbance for those who were sleeping. Apart from this, people are dependent on each other in many ways and different times of their sleeping would have deprived them of helping each other in their works because working time of one would have been the time of rest for the other.

If human beings would have resorted to a social contract for uniting the times of rest and work for the whole world, it was not, at the first place, an easy task to make billions of people agree on a single resolution, then the implementation of such a contract would have required a lot of formal departments, and still there would have been room for violation of such a contract through corrupt means, as is observed in the contemporary forums. All such problems have been overcome by the creation of night and sleep by Allah Ta’ ala which are greatly beneficial and necessary for human and other living beings. Allah Ta’ ala has instilled in humans such an urge to sleep at night that one can keep awake only with great difficulty and effort. فَتَبَارَ‌كَ اللَّـهُ أَحْسَنُ الْخَالِقِينَ

Similarly in وَجَعَلَ النَّهَارَ‌ نُشُورً‌ا (and has made the day a means of revival - 25:47), the day is described as revival, because its opposite, that is sleep, is like death when one loses all his senses. Here again, to keep awake and attend to one's needs during the day time is made mandatory in human beings. If this was not so, some people would have attended to their work while others slept, and this would have caused all sorts of problems.

As in the case of sleep, Allah Ta’ ala has bestowed a great blessing on human beings by creating its need at night. He has also made it part of human nature to keep awake and attend to work during day time, so that people should look after each other's needs. He has also fixed certain timings for certain desires and needs common in all human beings. For instance, all people feel hungry in the mornings and evenings and want to eat. So the eating times of all humans are common which is again a great blessing from Allah Ta’ ala