وَاللَّهُ خَلَقَكُمْ ثُمَّ يَتَوَفَّاكُمْ ۚ وَمِنكُم مَّن يُرَدُّ إِلَىٰ أَرْذَلِ الْعُمُرِ لِكَيْ لَا يَعْلَمَ بَعْدَ عِلْمٍ شَيْئًا ۚ إِنَّ اللَّهَ عَلِيمٌ قَدِيرٌ (70)
(16:70) And consider this: Allah created you: then He causes your death; *60 and some one from among you is carried on to abject old age so that after knowing all he could, he may no longer have any knowledge of it. *61 The fact is that Allah alone is All-Knowing, All-Powerful.
*60) It is to emphasize this: Allah not only provides you with the necessities and good things of life (as stated in the preceding verses), but also has full power over your life and death. None else has any power to give lift or cause death.
*61) This fact has been mentioned to bring home to the disbelievers and the mushriks that knowledge, which gives superiority to man over all creatures on this Earth, has been given by Allah, as if to say, "You yourselves have seen that when a man, who once possessed much knowledge, becomes very old, he is reduced to a mere lump of flesh. Then that man who once taught knowledge to others loses all his senses and cannot look even after his own self".