﴿ فَلَآ أُقْسِمُ بِرَبِّ ٱلْمَشَٰرِقِ وَٱلْمَغَٰرِبِ إِنَّا لَقَٰدِرُونَ ﴾

“But nay! I call to witness [Our being] the Sustainer of all the points of sunrise and sunset: verily, well able are We”

The periodic change in the places where the sun rises and sets on the earth’s horizon is due to that unique feature of the earth known as the axial tilt. This plus the fact that the sun is at one of the foci of the earth’s elliptical orbit, and not at its centre, is responsible for the changing of the seasons. In the absence of such factors the earth would have been less useful to man.