(As in the life of humankind, “days” and “nights” alternate in the world, also.) We have made the night and the day two signs (manifesting the truth of God’s Power, Knowledge, and absolute sovereignty, and His grace on you). We have obscured the sign of the night (made it dark), and We have made the sign of the day illuminating (therefore, a means for you) to see,
that you may seek bounty from your Lord, and that you may know the computation of (time) the years and the reckoning; We set out all things in clear detail.
The following excerpt is taken from “The Quran with Annotated Interpretation” by Ali Unal pg. 533 note 9:
According to Ibn ‘Abbās, the sign of the night refers to the moon, and the sign of the day, to the sun. Therefore, from the words, We have obscured the sign of the night, we might infer that the moon once emitted light as the sun does and God took its light from it, causing it to darken, or obscuring it. Or, we could infer that the solar system was a single mass, later dividing into the sun and its satellites. While the verse thus recounts the past of the
moon, it also points to the future destiny of all heavenly bodies.
The following excerpt is taken from “In the Shade of the Quran” by Syed Qutb al isra (sura 17) pg. 109-110:
The universal law that governs the succession of day and night is linked to
numerous aspects of human life. It is linked with people’s efforts in earning their living, and their knowledge of time and calculation. It also relates to the good and evil man may earn in life and what reward he may achieve in the end for either his good or bad actions. Indeed the consequences of following guidance or error relate to it, as is the individual nature of responsibility which means that no one will have to answer for anyone else. The same universal law is linked to God’s promise that He will not inflict punishment on anyone until He has sent His messengers. This link further applies to the law which governs the destruction of communities only after the affluent among them have been guilty of immense transgression. The law further relates to the diverse destinies of those who seek the pleasures of this world and those who prefer the good reward of the hereafter, and what God grants to both in this life and in the life to come. All these aspects follow a well set system and certain immutable laws besides. Nothing takes place haphazardly.
Qutb. In the Shade of the Quran. (Al Isra [sura 17] pg. 109-110). http://www.islamicweblibrary.com/wp-content/uploads/2020/09/Full-Vol.pdf
Unal, Ali (2006). The Quran with Annotated Interpretation in Modern English. http://www.islamicweblibrary.com/wp-content/uploads/2020/07/The-quran-with-annotated-interpretation-.pdf