As Messiah begins to conclude his teaching on the last days he addresses the disciples question, "What will be the sign of your coming?" (Matthew 24:3). Messiah mentions 5 things will occur.
First, there will be a complete blackout of the heavens (Matthew 24:29). The sun, moon, stars, and heavenly bodies will not shine their light.
Second, this heavenly phenomena along with the roaring and churning of the seas will effect all of humanity immensely. Luke tells us the inhabitants of the earth will experience great stress, anxiety, perplexity, and confusion. The terror will be so gripping stout hearted men will cower in great fear and agitation (Luke 21:25-26).
Third, the sign of the Son of Man will appear in the sky. The sign is the Shekinah glory. Messiah does say he will come on the clouds of heaven with power and great glory (Matthew 24:30). The glory is the Shekinah, the glory of the heavenly Father (Matthew 16:27).
Fourth, the twelve tribes of Israel, that is the Jewish people will mourn (Matthew 24:30). They will mourn over the national rejection of Yeshua as Messiah. They will mourn (Zechariah 12:10) and God in his mercy and grace will forgive them of their sin and cleanse them of all unrighteousness (Zechariah 13:1).
Fifth, Messiah with the sound of the shofar will send out his angels to the four corners of the earth to regather his people Israel back to their own Land (Matthew 24:31; Isaiah 27:12-13).
YouTube: https://www.youtube.com/watch?v=ke1pYO5InZY&t=26s