At the time of the Prophet, the companions were very concerned about the end times and even considered their times as the end times.
This turned out to have a tremendous impact on increasing their faith as well as being a trigger and trigger in the good deeds of friends. Currently we are in the fourth phase of the five phases of the life of Muslims. At the end of this phase some signs of the end of time will appear, among them are Ad dukhon or thick hot smoke that envelops humans for 40 days so that we cannot see anything because of the pitch blackness.

May be useful.