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What did Allah (SWT) do on the Day of Arafah?
﴿الْيَوْمَ أَكْمَلْتُ لَكُمْ دِينَكُمْ وَأَتْمَمْتُ عَلَيْكُمْ نِعْمَتِى وَرَضِيتُ لَكُمُ الأِسْلاَمَ دِيناً﴾
(This day, I have perfected your religion for you, completed My favor upon you, and have chosen for you Islam as your religion.) This, indeed, is the biggest favor from Allah to this Ummah, for He has completed their religion for them, and they, thus, do not need any other religion or any other Prophet except Muhammad .