Sahih al-Bukhari #3436

Narrated Hudhaifa: Once `Umar bin Al-Khattab said, said, "Who amongst you remembers the statement of Allah's Apostle regarding the afflictions?" Hudhaifa replied, "I remember what he said exactly." `Umar said. "Tell (us), you are really a daring man!'' Hudhaifa said, "Allah's Messenger (ﷺ) said, 'A man's afflictions (i.e. wrong deeds) concerning his relation to his family, his property and his neighbors are expiated by his prayers, giving in charity and enjoining what is good and forbidding what is evil.' " `Umar said, "I don't mean these afflictions but the afflictions that will be heaving up and down like waves of the sea." Hudhaifa replied, "O chief of the believers! You need not fear those (afflictions) as there is a closed door between you and them." `Umar asked, "Will that door be opened or broken?" Hudhaifa replied, "No, it will be broken." `Umar said, "Then it is very likely that the door will not be closed again." Later on the people asked Hudhaifa, "Did `Umar know what that door meant?" He said. "Yes, `Umar knew it as everyone knows that there will be night before the tomorrow morning. I narrated to `Umar an authentic narration, not lies." We dared not ask Hudhaifa; therefore we requested Masruq who asked him, "What does the door stand for?" He said, "`Umar."