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Surah 31. Luqman
Ayah 29 - 30
٢٩. أَلَمْ تَرَ أَنَّ ٱللَّهَ يُولِجُ ٱلَّيْلَ فِى ٱلنَّهَارِ وَيُولِجُ ٱلنَّهَارَ فِى ٱلَّيْلِ وَسَخَّرَ ٱلشَّمْسَ وَٱلْقَمَرَ كُلٌّ يَجْرِىٓ إِلَىٰٓ أَجَلٍ مُّسَمًّى وَأَنَّ ٱللَّهَ بِمَا تَعْمَلُونَ خَبِيرٌ
٣٠. ذَٰلِكَ بِأَنَّ ٱللَّهَ هُوَ ٱلْحَقُّ وَأَنَّ مَا يَدْعُونَ مِن دُونِهِ ٱلْبَـٰطِلُ وَأَنَّ ٱللَّهَ هُوَ ٱلْعَلِىُّ ٱلْكَبِيرُ
29. See you not that Allah merges the night into the day, and merges the day into the night, and has subjected the sun and the moon, each running its course for a term appointed; and that Allah is All-Aware of what you do. 30. That is because Allah, He is the Truth, and that which they invoke besides Him is falsehood; and that Allah, He is the Most High, the Most Great.
(merges the night into the day,) meaning, He takes from the night and adds to the day, so that the day becomes longer and the night shorter, which is what happens in summer when the days are longest; then the day starts to become shorter and the night longer, which is what happens in winter.
(and has subjected the sun and the moon, each running its course for a term appointed;) It was said that this means, each runs within its set limits, or it means until the Day of Resurrection; both meanings are correct. The first view is supported by the Hadith of Abu Dharr, may Allah be pleased with him, in the Two Sahihs, according to which the Messenger of Allah said:
(O Abu Dharr! Do you know where this sun goes) I (Abu Dharr) said: "Allah and His Messenger know best.'' He said:
(It goes and prostrates beneath the Throne, then it seeks permission from its Lord, and soon it will be said: "Go back from whence you came.'') Ibn Abi Hatim recorded that Ibn `Abbas said, "The sun is like flowing water, running in its course in the sky during the day. When it sets, it travels in its course beneath the earth until it rises in the east.'' He said, "The same is true in the case of the moon.'' Its chain of narration is Sahih.
(and that Allah is All-Aware of what you do.) This is like the Ayah,
(Know you not that Allah knows all that is in the heaven and the earth) (22:70). The meaning is that Allah is the Creator Who knows all things, as He says:
(It is Allah Who has created seven heavens and of the earth the like thereof) (65:12).
(That is because Allah, He is the Truth, and that which they invoke besides Him is falsehood;) means, He shows you His Signs so that you may know from them that He is the Truth, i.e., He truly exists and is truly divine, and that all else besides Him is falsehood. He has no need of anything else, but everything else is dependent on Him, because everything in heaven and on earth is created by Him and is enslaved by Him; none of them could move even an atom's weight except with His permission. If all the people of heaven and earth were to come together to create a fly, they would not be able to do so. Allah says:
(That is because Allah, He is the Truth, and that which they invoke besides Him is falsehood; and that Allah, He is the Most High, the Most Great.) meaning, He is the Most High and there is none higher than Him, and He is the Most Great Who is greater than everything. Everything is subjugated and insignificant in comparison to Him.