Revelation 1:[1] The Revelation of Jesus Christ, which God gave unto him, to shew unto his servants things which must shortly come to pass; and he sent and signified it by his angel unto his servant John:
[2] Who bare record of the word of God, and of the testimony of Jesus Christ, and of all things that he saw.
[3] Blessed is he that readeth, and they that hear the words of this prophecy, and keep those things which are written therein: for the time is at hand.
[4] John to the seven churches which are in Asia: Grace be unto you, and peace, from him which is, and which was, and which is to come; and from the seven Spirits which are before his throne;
[5] And from Jesus Christ, who is the faithful witness, and the first begotten of the dead, and the prince of the kings of the earth. Unto him that loved us, and washed us from our sins in his own blood,
[6] And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen.
[7] Behold, he cometh with clouds; and every eye shall see him, and they also which pierced him: and all kindreds of the earth shall wail because of him. Even so, Amen.
[8] 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.

Rev.1:[8] 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.

The first thing we should know about Jesus Christ is this: Jesus Christ is God!!! He is the beginning of everything without Him was made that was made. Jesus as God is Eternal. There has never been a time when He was NOT. In order to erase any doubt whatsoever the Bible clearly tells us here JESUS IS THE ALMIGHTY! There is no limit to His power or authority.
(John 1:1-3)

5a And from Jesus Christ, who is the faithful witness,
God sent His Son to the nation of Israel to witness to them of God (John 5:31-39)
The Bible tells us in John chapter one He came to the nation of Israel but they rejected Him. (John 1:10-12)
Rather than receive Him at that time as King they crucified Him. Unaware this proved to be the saving of the world.

5b and the first begotten of the dead,

After being crucified He went to Hell for the sin of the world because He Himself had no sin. But God raised Him out of Hell and brought Him out that He might be the firstborn of many creatures. (Colossians 1:15) Assuming His role as High Priest making intercession for our sins. (Hebrews 4:14-5:5, 7:25-28)

Revelation 1:[18] I am he that liveth, and was dead; and, behold, I am alive for evermore, Amen; and have the keys of hell and of death.

Upon His Resurrection garnering the keys of death and Hell. Rescuing us from the fear of death.
(Hebrews 2:14-15)

5d Unto him that loved us, and washed us from our sins in his own blood,

Through His shed blood purchasing us and paying the price for our sins. Motivated by His love willing to sacrifice Himself for us. (Romans 5:7-10//Colossians 1:14/// Ephesians 1:7)

[7] Behold, he cometh with clouds; and every eye shall see him, and they also which pierced him: and all kindreds of the earth shall wail because of him. Even so, Amen.

When He returns to the earth it will be to rescue the Jewish people and destroy the anti-Christ. The nation of Israel will look on Jesus and recognize He is the one whom their forefathers rejected and crucified. The whole world will cry out because He has returned and will execute judgment upon mankind.
(Zechariah 12:10-14)

5c and the prince of the kings of the earth.
Upon His return He will assume His rightful position over all of creation. He sits now at the right hand of the Father waiting for the world to be placed under Him. (1 Corinthians 15:24-28 Hebrews 2:5-15)

[6] And hath made us kings and priests unto God and his Father; to him be glory and dominion for ever and ever. Amen.
When He assumes His throne over all of the earth we too shall be placed in positions of authority and also shall reign with Him over the remaining peoples of the earth.

So we see in Revelation One the story of Jesus Christ. He who existed in eternity past came in the flesh, died for our sin, resurrected for our salvation delivering us from the power of death having paid the penalty for our sin. He currently waits for His triumphant return to assume His rightful position over the world which He will rule with a rod of iron.