Charles Spurgeon Commentary Revelation 1:8-12

"I am the Alpha and the Omega, saith the Lord God, who is and who was and who is to come, the Almighty. I John, your brother and partaker with you in tribulation and kingdom and patience [which are] in Jesus, was in the isle that is called Patmos, for the word of God and the testimony of Jesus. I was in the Spirit on the Lord`s day, and I heard behind me a great voice, as of a trumpet saying, What thou seest, write in a book and send [it] to the seven churches: unto Ephesus, and unto Smyrna, and unto Pergamum, and unto Thyatira, and unto Sardis, and unto Philadelphia, and unto Laodicea. And I turned to see the voice that spake with me. And having turned I saw seven golden candlesticks;" — Revelation 1:8-12 (ASV)

I am Alpha and Omega, the beginning and the ending, saith the Lord, which is, and which was, and which is to come, the Almighty. I John, who also am your brother, and companion in tribulation, and in the kingdom and patience of Jesus Christ, was in the isle that is called Patmos, for the word of God, and for the testimony of Jesus Christ. I was in the Spirit on the Lord's day, and heard behind me a great voice, as of a trumpet, saying, I am Alpha and Omega, the first and the last: and, What thou seest, write in a book, and send it unto the seven churches which are in Asia; unto Ephesus, and unto Smyrna, and unto Pergamos, and unto Thyatira, and unto Sardis, and unto Philadelphia, and unto Laodicea. And I turned to see the voice that spake with me.

This was a very natural thing for John to do. We always feel a desire to see who it is that addresses us, and especially would this be the case if we heard such a sentence as this, spoken with a trumpet voice by One who could truly say it, I am Alpha and Omega, the first and the last. Who would not have turned to see such a Speaker? I am sure that John would, for he must have recognized that voice, though it was pitched in a higher key than usual, and was full of more sonorous force than when he last heard it. He must have known the voice of the Well-beloved as he spoke again to his highly-favored servant.