Asim (may Allah have mercy on him) narrated that I asked Sayyiduna Anas (may Allah be pleased with him), "Did the Messenger of Allah (peace and blessings of Allah be upon him) declare Madinah Munawwarah a sacred city?" He replied, "Yes, from such-and-such a place (Ayr) to such-and-such a place (Thur), no tree of this area should be cut. Whoever introduces a new thing within these boundaries, upon him is the curse of Allah, His angels, and all mankind." Asim said that then Musa bin Anas informed me that Sayyiduna Anas (may Allah be pleased with him) also stated that, "or whoever gives refuge to an innovator in religion."