What does Revelation 6:12 mean?
This verse tells us the first phenomenon John saw and heard when Jesus (Revelation 5:6–8) opened the sixth seal. He said a great shaking occurred, a total eclipse of the sun took place, and the moon turned bloodlike. Since the description of the four horsemen (Revelation 6:1–11) seems more of a metaphor than a prediction of four actual riders, some think this verse represents political, civil, and social chaos.On the other hand, there are reasons to take John's vision here as a description of literal events, or at least as a reference to actual natural disasters. A horrendous shaking can occur and cause colossal earthquakes and extensive damage-causing tsunamis. Total eclipses of the sun occur regularly, though they're not always easily-visible for most people on earth. Certain natural disasters can cause clouds of dust to block out the sun's light from large regions. Similar conditions might cause the moon to appear various colors, including a bloody red. It is not hard to imagine the panic these events might cause, especially if they occur in close proximity to each other.
In addition, a more-literal interpretation of this particular passage seems to match the words of Jesus. In his Olivet Discourse, Jesus predicted the tribulation calamities that occur when the Lamb opens the seals. He said, "Nation will rise against nation, and kingdom against kingdom, and there will be famines and earthquakes in various places…Then they will deliver you up to tribulation and put you to death…Immediately after the tribulation of those days the sun will be darkened, and the moon will not give its light." (Matthew 24:7–9, 29). The events that transpire under the sixth seal seem to echo Jesus' words.