Narrated `Aisha:Allah's Messenger (ﷺ) in his fatal illness said, "Allah cursed the Jews and the Christians, for they built the places of worship at the graves of their prophets." And if that had not been the case, then the Prophet's grave would have been made prominent before the people. So (the Prophet (ﷺ) ) was afraid, or the people were afraid that his grave might be taken as a place for worship
لَمَّا سَقَطَ عَلَيْهِمُ الْحَائِطُ فِي زَمَانِ الْوَلِيدِ بْنِ عَبْدِ الْمَلِكِ أَخَذُوا فِي بِنَائِهِ، فَبَدَتْ لَهُمْ قَدَمٌ فَفَزِعُوا، وَظَنُّوا أَنَّهَا قَدَمُ النَّبِيِّ صلى الله عليه وسلم فَمَا وَجَدُوا أَحَدًا يَعْلَمُ ذَلِكَ حَتَّى قَالَ لَهُمْ عُرْوَةُ لاَ وَاللَّهِ مَا هِيَ قَدَمُ النَّبِيِّ صلى الله عليه وسلم مَا هِيَ إِلاَّ قَدَمُ عُمَرَ ـ رضى الله عنه ـ.
Narrated `Urwa:When the wall fell on them (i.e. graves) during the caliphate of Al-Walid bin `Abdul Malik, the people started repairing it, and a foot appeared to them. The people got scared and thought that it was the foot of the Prophet. No one could be found who could tell them about it till I (`Urwa) said to them, "By Allah, this is not the foot of the Prophet (ﷺ) but it is the foot of `Umar