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Surah 9. Al-Tawba
Ayah 28
28 يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوٓا۟ إِنَّمَا ٱلْمُشْرِكُونَ نَجَسٌ فَلَا يَقْرَبُوا۟ ٱلْمَسْجِدَ ٱلْحَرَامَ بَعْدَ عَامِهِمْ هَـٰذَا ۚ وَإِنْ خِفْتُمْ عَيْلَةً فَسَوْفَ يُغْنِيكُمُ ٱللَّهُ مِن فَضْلِهِۦٓ إِن شَآءَ ۚ إِنَّ ٱللَّهَ عَلِيمٌ حَكِيمٌ
[28] O Believers, the mushriks are unclean; therefore let them not come near the Masjid-i-Haram25 after this year (of their pilgrimage); if you fear poverty Allah will enrich you, out of His bounty if He wills: for Allah is All-knowing, All-Wise.
25This prohibition was meant to root out all the vestiges of shirk and ' ignorance' . For the mushriks were prohibited not only from the performance of Haj and attendance at the Masjid-i-Haram but also from entering into its sacred precincts .
They are "unclean" in their creeds, in their morals, in their deeds, and in their ways of `ignorance', and not in their physical bodies by themselves. That is the reason why they have been prohibited from entering the sacred precincts of the Holy Place.
This prohibition has been interpreted in different ways. Imam Abu Hanifah is of the view that it prohibits them only from the performance of Haj and Umrah, and from the observance of the rites of `ignorance' in the Holy Precincts. But Imam Shafi`i is of the opinion that they have been forbidden even to enter the Masjid-i-Haram for any purpose whatsoever. Imam Malik is of the opinion that they are forbidden not only to enter Masjid-i-Haram but any mosque at all. It is, however, obvious that the last opinion is not correct, as the Holy Prophet himself permitted mushriks to enter the Prophet's Mosque at Al-Madinah.