Sayyidina Hudhayfah (RA) reported that Sayyidina Umar (RA) . asked, “Which of you remembers the sayings of Allah’s Messenger (SAW) about fitnah?” So he Hudhayfah said, “I.” He then narrated, “The trial of a man lies in his family, wealth, children and neighbours (concerning rights attached to them which he violates). They are atoned by salah, fasting, sadaqab, enjoining righteousness and forbidding evil.” Umar (RA) said, “This is not what I asked. I asked about the trial and commotion that will rise like waves of the ocean.” He said, O Amir-ul-Mumineen (Commander of the faithful), there is between you and it a closed door.” Umar asked, “Will it he opened or broken?” He said, “It will be broken.” So, hesaid, “in that case, it will not be closed till the Last Hour.’ Abu Wail said in the hadith of Hammad that he said to Masruq, “Ask Hudhayfah, what is the door ?“ He said, “That is Umar (RA) himself
[Bukhari 525,Muslim 144]
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