What did Abu Bakr do on the day of Nahr to ensure that no pagan performed the Hajj that year according to the hadith of Prophet Muhammad (saw)?
 Narrated Abu Huraira:                     Abu Bakr, on the day of Nahr (i.e. slaughtering of animals for sacrifice), sent me in the company of others to make this announcement: "After this year, no pagan will be allowed to perform the Hajj, and none will be allowed to perform the Tawaf of the Ka`ba undressed." And the day of Al-Hajj-ul-Akbar is the day of Nahr, and it called Al-Akbar because the people call the `Umra Al-Hajj-ul-Asghar (i.e. the minor Hajj). Abu Bakr threw back the pagans' covenant that year, and therefore, no pagan performed the Hajj in the year of Hajj-ul-Wada` of the Prophets.