The book of Revelation is written by John, one of Jesus’ followers. It is a recording of visions John experienced while in exile on an island named Patmos. The visions are addressed to seven churches located in what we call Turkey today and tell of things which will happen in the future. Although the events described are clearly in the future when John writes them down, there is debate over which ones are in the past or future for us living 2000 years later. As is typical for people who see visions of heavenly beings, John is overwhelmed. He is told not to be afraid and to write down the things he sees.
The one talking to John is Jesus, in His heavenly form. Although John had been close to Jesus when He was in human form, John is now terrified by Him. Jesus is both our close friend and God. We have the privilege of knowing Him and loving Him, but also to honor Him.