Sunan At-Tirmidhi

Abu Wa'il narrated from Hudhaifah that 'Umar said:""Which of you remembers what the Messenger of Allah(s.a.w) said about the Fitnah?"" So Hudhaifah said: ""I do."" Hudhaifah said: ""A man's Fitnah is in his family, his wealth, his children, and his neighbors. It is atoned for by the Salat, fasting, charity, and by commanding good and forbidding evil."" 'Umar said: ""I am not asking you about this. Rather, about the Fitnah that spreads like the waves of the sea."" He said: ""O Commander of the Believers! Between you and it is a closed door."" 'Umar said: ""Will it be opened or broken?"" He said: ""It will be broken."" He said: ""Then it will never be closed until the Day of Judgement