Answer
Once, as Jesus was leaving the temple in Jerusalem, His disciples observed the buildings. Jesus took that opportunity to inform them about future events, including discussing the sign of the Son of Man “and then the sign of the Son of man will appear in heaven, and all the tribes of the earth will mourn, and they will see the Son of man coming in the clouds of heaven with power and great glory.”, (Matthew 24:30). This marked the beginning of Jesus’ prophetic speech on the Mount of Olives, commonly known as the Olivet Discourse (Matthew 24).
When the disciples pointed out the temple complex buildings “And Jesus went out, and departed from the temple: and his disciples came to him to show him the buildings of the temple.”, (Matthew 24:1), Jesus mentioned that every stone would be destroyed “And Jesus said to them, ‘Do you not see all these things? Truly I tell you, not one stone here will be left on another; every one will be thrown down.'”, (Matthew 24:2). Curious, the disciples asked Him two questions: 1) when these events would occur and 2) what would signal His return and the end of the age “And as he sat on the Mount of Olives, the disciples came to him privately, saying, ‘Tell us, when will these things happen, and what will be the sign of your coming and of the end of the world?'”, (Matthew 24:3). Jesus then proceeded to predict future events, confirming that the sign of the Son of Man would indeed appear “and then the sign of the Son of Man will appear in heaven, and all the tribes of the earth will mourn when they see the Son of Man coming on the clouds of heaven with power and great glory.”.
Behold the sign of the Son of Man in heaven: and then all the tribes of the earth will mourn, and they will see the Son of Man coming in the clouds of heaven with power and great glory.” , (Matthew 24:30).
Initially, Jesus warns them not to be deceived by false messiahs or to believe that they had reached the final days of the age (Matthew 24:4-8). Wars and rumors of wars, famines, and earthquakes would only be the beginning of “birth pangs” leading to the end. The disciples would face persecution and death, being hated by all because of Jesus’ name “Then they will deliver you up to tribulation and put you to death, and you will be hated by all nations for my name’s sake.” , (Matthew 24:9). However, that would not be the end. Many would fall away, betrayal and hatred would increase, and false prophets would appear (Matthew 24:10-11). Lawlessness would rise, and love would diminish “And because lawlessness will be increased, the love of many will grow cold.” , (Matthew 24:12). Jesus mentions that those who endure until the end will be saved, and the gospel of the kingdom will be proclaimed to all nations. Then the end will come (Matthew 24:13-14). When comparing other passages with the Olivet Discourse, we observe Jesus transitioning in His narrative from describing an unspecified period to a three-and-a-half-year duration leading to the sign of the Son of Man.
Jesus cautions that when they witness the abomination of desolation, they should flee toThe mountains. This abomination is described in Daniel 9:27, 11:31, and 12:11 as taking place in the midpoint of the final seven years of the prophetic calendar. That event will herald a great tribulation unlike anything before or after (Matthew 24:15-21). Jesus tells the disciples these things ahead of time so they will not be misled by false prophets and false messiahs, some of whom will even show great signs and wonders (Matthew 24:23-26). When Jesus returns to the earth to establish His kingdom, it will be obvious to all—like lightning that flashes across the sky “For as the lightning cometh out of the east, and shineth even unto the west; so shall also the coming of the Son of man be.”, (Matthew 24:27). After that time and the dreadful events that take place, the heavens will be greatly disturbed “Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken:”, (Matthew 24:29), and then the sign of the Son of Man will appear “and then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory.”, (Matthew 24:30). All people will see Him coming with power and glory “and then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory.”, (Matthew 24:30), and He will return.
In this context, Jesus does not explain what exactly the sign of the Son of Man is, and the disciples do not ask for any further explanation. Earlier, the Pharisees, after clearly rejecting Jesus, had demanded yet another sign from Him. He explained that they would have no further sign but the sign of Jonah, which indicated that the Messiah would be buried for three days (Matthew 12:38-40). Again, they demanded a sign in Matthew 16:1, and He reiterated that they would only receive the sign of Jonah. False messiahs and false prophets would perform signs to deceive people into believing they were genuine, but the true sign pointing to the Son of Man—the rightful Messiah King—would not be evident until the appropriate time. It appears that even by the disciples’ question, they understood that Jesus’ return itself was the sign. It was the proof, the miracle that would conclusively demonstrate Jesus’ true identity. The sign that would reveal His authenticity for all to see is the Son of Man coming in the clouds of the sky with power and great glory «and then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory. », (Matthew 24:30).