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Surah 36. Yasin
Ayah 66 - 68
66 وَلَوْ نَشَآءُ لَطَمَسْنَا عَلَىٰٓ أَعْيُنِهِمْ فَٱسْتَبَقُوا۟ ٱلصِّرَٰطَ فَأَنَّىٰ يُبْصِرُونَ
67 وَلَوْ نَشَآءُ لَمَسَخْنَـٰهُمْ عَلَىٰ مَكَانَتِهِمْ فَمَا ٱسْتَطَـٰعُوا۟ مُضِيًّا وَلَا يَرْجِعُونَ
68 وَمَن نُّعَمِّرْهُ نُنَكِّسْهُ فِى ٱلْخَلْقِ ۖ أَفَلَا يَعْقِلُونَ
[66-68] If We will, We can put out their eyes: then let them strive to seek the way. From where will they see it? If We please, We can so transform them in their places that they would neither be able to go forward nor turn backward.56 Whomsoever We grant a long life, We just reverse him in nature and constitution.57 Do they not understand anything (from this)?
56After depicting the scene of Resurrection, the people are being warned to this effect: "The Resurrection may seem yet far off to you, but even if you consider seriously your life in this world of which you are so proud, you will see how helpless you are in the powerful grip of Allah. Your eyes by virtue of whose sight you are carrying out all your obligations in the world can be blinded at one command of Allah. Your legs on whose strength you are showing All this activity can become paralyzed as and when Allah wills. As long as the powers and capabilities granted by Allah continue to function, you remain lost in the arrogance of your self, but as soon as one of them fails to function, you come to understand how helpless you are!"
57"Reverse him in nature," means that in old age Allah turns him back to the state of childhood. He becomes unable to stand and walk without the help and support of others; he is fed by others; he urinates and defecates in bed; talks childishly and is laughed at by others. In short, towards the end of life he returns to the same state of weakness with which he had started lift in this world."