Hadith 12:

It was narrated from Jundub ibn Abdillah ibn Sufyan al-Bajali that he said: I heard the Prophet (s.a.w) say five days before he died: «I deny before Allah that I have any Khaleel (close,intimate friend) among you, for Allah Azza wa Jalla has taken me as a khaleel as He took Ibrahim as a khaleel. If I were to take any khaleel from among my ummah, I would have taken Abu Bakr as a khaleel. Indeed, those who came before you used to take the graves of their prophets and righteous men as places of worship. Do not take graves as places of worship; I forbid you to do that.»