This is a revelation from  Jesus Christ, which God gave him concerning the events that will happen soon. An angel was sent to God's servant John so that John could share the revelation with God's other servants. John faithfully reported the word of God and the testimony of Jesus Christ – everything he saw.  Rev1:1-2.

I am John, your brother. In Jesus we are partners in suffering and in the Kingdom and in patient endurance. I was exiled to the island of Patmos for preaching the word of God and speaking about Jesus. It was the Lord's Day, and I was worshiping in the Spirit. Suddenly, I heard a loud voice behind me, a voice that sounded like a trumpet blast.  It said, "Write down what you see, and send it to the seven churches: Ephesus, Smyrna, Pergamum, Thyatira, Sardis, Philadelphia, and Laodicea." Rev 1:9-11

                                   Patmos, Greece