The first part of Revelation is a letter written to the seven churches in Asia(modern Turkey). The purpose of this letter was to encourage and challenge the churches, and to give to them the prophecy that John has received from Jesus.
This is from the New International version of Revelation
Revelation 1
Prologue
1 The revelation from Jesus Christ, which God gave him to show his servants what must soon take place. He made it known by sending his angel to his servant John, 2 who testifies to everything he saw—that is, the word of God and the testimony of Jesus Christ. 3 Blessed is the one who reads aloud the words of this prophecy, and blessed are those who hear it and take to heart what is written in it, because the time is near.This prologue is a note by John telling the readers of this letter that he has received a revelation about the future from Jesus, through an angel and he is passing it on to the recipients of the letter. He also bestows a blessing on the readers of the prophecy and on those that hear it and take it to heart.
Greetings and Doxology
4 John, To the seven churches in the province of Asia:Grace and peace to you from him who is, and who was, and who is to come, and from the seven spirits[a] before his throne,5 and from Jesus Christ, who is the faithful witness, the firstborn from the dead, and the ruler of the kings of the earth.
To him who loves us and has freed us from our sins by his blood, 6 and has made us to be a kingdom and priests to serve his God and Father—to him be glory and power for ever and ever! Amen.
7 “Look, he is coming with the clouds,”[b]
and “every eye will see him,
even those who pierced him”;
and all peoples on earth “will mourn because of him.”[c]
So shall it be! Amen.
8 “I am the Alpha and the Omega,” says the Lord God, “who is, and who was, and who is to come, the Almighty.”
The second part of the letter is a greeting to the churches that will receive the letter. John greets them in the name of the trinity. Him who is, was, and is to come is God; from the seven spirits before his throne stand for the seven-fold Holy Spirit (seven stands for completeness); and from Jesus Christ who is the firstborn from the dead and the ruler of the kings of the earth. Jesus was the first to rise from the dead and confirm His deity. He also proclaims that Jesus has freed us from our sins by His sacrifice and His blood, He has made us to be priests to serve God. John then praises Him by saying to Him be the Glory and power forever and ever, and ends with Amen.
After this John gives us the first prophecy in verse. John predicts the return of Christ. He will not come the way He first came, quietly. This time when He returns it will be in the sky among the clouds, in glory. It will not be hidden, but every eye shall see Him. When John refers to "even those who pierced Him" he is talking about all those that have rejected Christ, they will mourn when they realize that He had returned and will judge them. Before John begins to describe the first vision he has been shown he lets the reader know from whom the visions have come. From God, the alpha and omega, which means He was there in the beginning and He will be the end. He who was and is and is to come. He has been in control since the beginning and He will be in control in the future. The Almighty- no one can stand against Him.
