I looked when He opened the sixth seal, and behold, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became like blood.
As we saw last week, the seals of Revelation 6 parallel the Olivet Prophecy Jesus Christ gave in Matthew 24. The fifth seal represented martyrdom of the saints and the Great Tribulation. The sixth seal represents the heavenly signs Jesus mentioned in Matthew 24:29.
These miraculous heavenly signs get the attention of people from all social classes (Revelation 6:15-16). These signs will spawn great fear and a desire to hide, but apparently not worldwide repentance (though a great multitude do repent and “come out of the great tribulation” as mentioned in Revelation 7:14). However, to finally bring all people to the point where they will listen, God will have to follow these signs with the “great day of His wrath” (Revelation 6:17), elsewhere called the Day of the Lord.
To read about why God is angry and the solution to these problems, see our article “Why Is God Angry With America?”