Allah said,

[رَبُّ الْمَشْرِقَيْنِ وَرَبُّ الْمَغْرِبَيْنِ ]

((He is) the Lord of the two easts and the Lord of the two wests.) meaning the sunrise of summer and winter and the sunset of summer and winter. Allah said in another Ayah,

[فَلاَ أُقْسِمُ بِرَبِّ الْمَشَـرِقِ وَالْمَغَـرِبِ]

(So, I swear by the Lord of all the points of sunrise and sunset in the east and the west.)(70:40), referring to the different places from which the sun rises and then sets on people every day. Allah said in another Ayah,

[رَّبُّ الْمَشْرِقِ وَالْمَغْرِبِ لاَ إِلَـهَ إِلاَّ هُوَ فَاتَّخِذْهُ وَكِيلاً ]

(The Lord of the east and the west; none has the right to be worshipped but He. So take Him alone as a trustee.)(73:9), referring to the different places of sunrise and sunset and the benefits that this variation brings to the created, mankind and Jinns,

[فَبِأَىِّ ءَالاءِ رَبِّكُمَا تُكَذِّبَانِ ]

(Then which of the blessings of your Lord will you both deny)