What does Revelation 8:2 mean?

According to verse 2, John saw seven angels stand before God and receive seven trumpets. These trumpets, as we learn later, signal catastrophes that occur on earth. It is significant that the seven angels do not begin the judgments without receiving the trumpets. Only God has the prerogative to judge sinners, so He gives the trumpets to the seven angels. The judgments that follow the trumpet blasts are meant to be especially significant to Israel, Jews who follow the dictates of the false prophet (Matthew 24:11–12; Revelation 13:1–18).

Much more so than a modern audience, Israel was familiar with trumpets. Trumpets summoned the nation to assemble, called upon soldiers to prepare for war, and signaled the beginning of festivals. Joel 2:1 predicts that the blowing of a trumpet will alert Israel to the approaching day of the Lord. Isaiah 27:13 promises that a great trumpet will summon Jews to leave their dispersion and return to Jerusalem to worship the Lord. Matthew 24:31 echoes this promise. Jesus said, "And he will send out his angels with a loud trumpet call, and they will gather his elect from the four winds, from one end of heaven to the other."