Jesus speaks of “those days” often.
He says, “But in those days, after that tribulation, the sun will be darkened, and the moon will not give its light, and the stars will be falling from heaven, and the powers in the heavens will be shaken.” (Mark 13: 24 – 25)
First, says Jesus, comes tribulation – terrible and final. “For in those days there will be such tribulation as has not been from the beginning of the creation that God created until now, and never will be.” (Mark 13: 19) False prophets and men who claim to be God appear, and deceive many. Nations rise up against each other as do brothers and sisters, parents and children.
In more ways than one, the world is dark when Jesus comes again. He prays that this time will not be in winter. He acknowledges that God, in His mercy, will cut short the tribulation “for the sake of the elect, whom He chose.” (Mark 13: 20)
When Jesus comes, angels will go out into heaven and into the world to “gather His elect.” (Mark 13: 27)
“Be on guard, keep awake. For you do not know when the time will come.” (Mark 13: 33)