Surah Al-Qasas Verse 71

3399 In the physical world the Night and Day are both blessings, the one for rest and the other for work, and the alternation itself is one of the mercies of Allah, and none but He can give us these blessings. If we were perpetually resting, or screened from the light, our faculties would be blunted and we should be worse than dead. If we were perpetually working, we should be tired, and we should also be dead in another way. This daily miracle keeps us alive and prepares us, in this our probationary life, for our final destiny in the Hereafter. So in the spiritual world. Some kinds of ignorance-such as ignorance of what is coming in the futureare necessary to conserve our powers and give rest to our minds and spirits, but if we were to remain ignorant perpetually, we should be spiritually dead. In the same way our spiritual strivings require periodical alternations to rest in the form of attention to our temporal concerns: hence the justification of a good and pure life on the plane of this earth also. Also, in the world's history, there are periods when a living messenger stimulates intense spiritual activity, and periods when it is comparatively quiescent (the so-called Dark Ages); but both are examples of the working of Allah's Plan of wisdom and mercy. But this applies only up to the Day of Judgement. After that we shall be on another plane altogether.