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Surah 30. Ar-Rum
Ayah 33 - 35
33وَإِذَا مَسَّ ٱلنَّاسَ ضُرٌّ دَعَوْا۟ رَبَّهُم مُّنِيبِينَ إِلَيْهِ ثُمَّ إِذَآ أَذَاقَهُم مِّنْهُ رَحْمَةً إِذَا فَرِيقٌ مِّنْهُم بِرَبِّهِمْ يُشْرِكُونَ
34لِيَكْفُرُوا۟ بِمَآ ءَاتَيْنَـٰهُمْ ۚ فَتَمَتَّعُوا۟ فَسَوْفَ تَعْلَمُونَ
35أَمْ أَنزَلْنَا عَلَيْهِمْ سُلْطَـٰنًا فَهُوَ يَتَكَلَّمُ بِمَا كَانُوا۟ بِهِۦ يُشْرِكُونَ
[33-35] When an affliction befalls the people, they invoke their Lord, turning penitently towards Him52 then when He makes them taste of His Mercy, some of them start committing shirk53 so that they may show ingratitude for Our favors. Well, enjoy yourselves, for soon you shall know. Have We sent down to them an authority, which may testify to the truth of the shirk they are committing?54
52This is a clear proof of the fact that in the depths of their heart there still exists an evidence of Tauhid. Whenever the hopes start crumbling, their hearts cry out from within that the real Ruler of the universe is its Master and His help alone can improve their lot.
53That is, "They again start presenting offerings before other deities, and claiming that their misfortune has been removed through the help and grace of such and such a saint and shrine."
54That is "What authority have they got to say that the calamities are not averted by God but by the so-called saint? Does common sense approve of it? Or, is there any Divine Book which says that Allah has delegated His powers to such and such saints, and that they should now be invoked by the people to help them out of difficulties?"