Matthew 24:21-22, 29-31

For at that time there will be a great tribulation (pressure, distress, oppression), such as has not occurred since the beginning of the world until now, nor ever will [again]. [Dan 12:1; Joel 2:2] And if those days [of tribulation] had not been cut short, no human life would be saved; but for the sake of the elect (God’s chosen ones) those days will be shortened.

“Immediately after the tribulation of those days THE SUN WILL BE DARKENED, AND THE MOON WILL NOT PROVIDE ITS LIGHT, AND THE STARS WILL FALL from the sky, and the powers of the heavens will be shaken. [Is 13:10; 34:4; Joel 2:10, 11; Zeph 1:15] And at that time the sign of the Son of Man [coming in His glory] will appear in the sky, and then all the tribes of the earth [and especially Israel] will mourn [regretting their rebellion and rejection of the Messiah], and they will see the SON OF MAN COMING ON THE CLOUDS OF HEAVEN with power and great glory [in brilliance and splendor]. [Dan 7:13; Rev 1:7] And He will send His angels with A LOUD TRUMPET and THEY WILL GATHER TOGETHER His elect (God’s chosen ones) from the four winds, from one end of the heavens to the other. [Is 27:13; Zech 9:14]