Pastor John Hagee stated that the four blood moons are a supernatural method for God to communicate with the world, and they signify something dramatic occurring involving the Middle East and Israel. He explores the events in his 2013 book "Four Blood Moons: Something Is About to Change."
Hagee refers to the tetrad, or group of four consecutive total lunar eclipses, of blood moons as celestial signals. The moon appears red during a blood moon. This blood moon is mentioned in multiple books of the Bible, including the book of Joel and the book of Acts. Hagee claims that God is aligning the sun, moon and earth for these blood moons.
Hagee gives examples of previous times during history when a tetrad of blood moons occurred on Jewish holidays, such as Passover and Sukkot. He says that each time coincided with events that started out as tragic for the Jewish people but became triumphant times by the end. Hagee doesn't describe any specific events, and he doesn't claim the 2014 and 2015 tetrad of blood moons coincides with the end times.
Critics of the blood moon theory point out that three of the four blood moons aren't visible in Israel. The Jewish calendar is also a lunar calendar, so one-sixth of all eclipses occur during Passover or Sukkot already. Hagee himself has been criticized for not giving appropriate credit to Mark Blitz, who created the blood moons theory in 2008 and shared it with Hagee in 2012.