جامع الترمذي

Nafi' narrated that a man came to Ibn 'Umar and said: "So-and-so conveys his Salam to you." So he said: "It has been conveyed to me that he has innovated, so if he has indeed innovated, then do not convey my Salam to him, for I heard the Messenger of Allah (s.a.w) saying: 'In this Ummah' or: 'In my Ummah'" - the doubt was his - "a collapse of the earth, or a transformation, or stones shall rain upon the people of Al-Qadr.'"