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Surah 38. Sad
Ayah 9 - 10
9 أَمْ عِندَهُمْ خَزَآئِنُ رَحْمَةِ رَبِّكَ ٱلْعَزِيزِ ٱلْوَهَّابِ
10 أَمْ لَهُم مُّلْكُ ٱلسَّمَـٰوَٰتِ وَٱلْأَرْضِ وَمَا بَيْنَهُمَا ۖ فَلْيَرْتَقُوا۟ فِى ٱلْأَسْبَـٰبِ
[9-10] The fact of the matter is that they doubt My "Admonition",10 and they say this because they have not yet tasted My punishment. Do they possess the treasures of the mercy of your Mighty and Bounteous Lord? Do they own the heavens and the earth and all that is between them? If so, let them climb up to the heights of the worldly means!11
10In other words Allah says: " Muhammad, these people are not belying you but Me. As for your truthfulness, they had never doubted it before; now that they are doubting it, it is because of My Admonition; now that I have entrusted to you the Mission of admonishing them, they have started doubting the truthfulness of the very person whose righteousness and piety they used to swear by " The same theme has also been discussed above in Al-An'am: 33 and E.N. 21 thereof.
11This is an answer to this saying of the disbelievers "Was he the only (fit) person among us to whom Allah's Admonition should have lien sent down?' Allah says: "it is for Us to decide whom We should choose and appoint as a Prophet and whom We should not. These people do not possess any power and authority to exercise choice in this regard. If they wish to attain such an authority they should try to reach the Divine Throne in order to obtain control over the office of sovereignty of the Universe, so that revelation should come down on him whom they regard as deserving their mercy and not on him whom We regard as fit for it. "This theme has occurred at several places in the Qur'an, because the unbelieving Quraish again and again said, `How did Muhammad (upon whom be Allah' peace) become a Prophet? Did Allah find no better man among the principal leaders of the Quraish worthy of this office?"(See Surah Bani Isra'il: . 00; Az-Zukhruf: 31-32).