Imām Bukhārī narrates: Musaddad narrated to us, he said: Yahyā narrated to us, from al-A'mash, he said: Shaqīq narrated to me, he said: I heard Hudhaifah, may Allāh be pleased with him, he said:

We were sitting with 'Umar, may Allāh be pleased with him. He asked: Does any of you remember the hadith of the Messenger of Allāh ﷺ regarding fitnah (tribulation)? I said: I remember it just as he said. (He said:) You have the courage for it. I said: The fitnah that occurs in a man's wife, his wealth, his children, and his neighbour is atoned for by prayer, fasting, sadaqah, commanding good and forbidding evil. 'Umar said: This is not what I mean, but I mean that fitnah whose waves will be like the waves of the sea. I said: O Amīr al-Mu'minīn! There is no danger to you from that fitnah; between you and that fitnah there is a locked door. 'Umar asked: Will that door be opened, or will it be broken? Hudhaifah said: It will be broken. 'Umar said: Then that door will never be closed again. We asked: Did 'Umar know that door? Hudhaifah said: Yes! Just as he knew that there is night before tomorrow (the day). I have narrated to him a hadith which is not a riddle. Then we ourselves were afraid to ask Hudhaifah, so we said to Masrūq, and he asked, so Hudhaifah told him: The door was 'Umar.