In Revelation 1:2 John describes himself as one who bore record of the word of God, the testimony of Jesus and all the things he saw (cf. 1John 1:1-4), and here tells us that blessings are pronounced upon all who read, believe and obey the testimony he reveals, about what was given to Jesus (Revelation 1:3). The reason folks were blessed, if they read, heard and heeded John’s testimony, was because its fulfillment was at hand. John’s readers were persecuted (cf. Revelation 1:9), and John’s testimony was to give them hope. He who endured would be blessed.
Are we able to keep or obey what we are unable to understand? It would be impossible to obey what seems to be uncertain. If we are unable to understand what John wrote, how is it possible to obey what he wrote down? Therefore, if believers are commanded to obey what the book says, it is logical to assume that first century readers must have been able to understand its contents. The book, therefore, couldn’t have been very mysterious to the believers in the first century AD. They understood its apocalyptic language most likely better than we do today.
There are seven blessings recorded by John in this book for those who read and hear what is written therein (Revelation 1:3; 14:13; 16:15; 19:9; 20:6; 22:7, 14)
The first blessing was one of hope (Revelation 1:3). In other words there was light at the end of the tunnel, because the persecution wouldn’t last forever, and not only so, but a reward would be given to those who read, considered and embraced John’s testimony. The word translated read (G314) means to know accurately, to distinguish between or recognize. In other words the blessing is upon folks who study in order to understand the book. The blessing is upon those who hear (G191) i.e. understand the words of the prophecy and keep (G5083) or guard them, because the time is at hand. Where there is no hope, one is left alone, abandoned to meet his troubles according to his own understanding (cf. Jeremiah 18:12; Ephesians 2:12), but we have Jesus’ promise that he would never leave us alone and forsake us to face our problems by ourselves (Hebrews 13:5).
The second blessing is pronounced on those who had given their lives to the sword rather than worship the beast or his image. In death they rest from their troubles, but their works follow them. In other words, they have a resurrection promised them and a reward for what they had done in Jesus’ name (Revelation 14:12-13), not so those who reject Jesus by embracing the beast and his image (Revelation 14:9-11). The blessing is that Jesus is a righteous Judge, and he will reward each man according to his works.
The third blessing (Revelation 16:15) is the blessing of satisfaction. Personally, I don’t think there is a pain worse than embarrassment. Physical pain will pass, and emotions are healed by time, but shame haunts one all of one’s life. To be little in another’s eyes is one thing, but to be little in one’s own eyes is almost indescribable. To be shamed for me is the ultimate punishment. Here, Jesus pronounces a blessing upon those who walk righteously in the face of trouble. He will not be ashamed of them (Luke 9:26; cf. Revelation 3:4).
The fourth blessing is offered to those who have been invited to the marriage supper of the Lamb (Jesus – Revelation 19:9). The Lord had been married to Israel, but he divorced her because she played the harlot and rejected him for her husband. At the Coming of Christ, the Church or Bride of Christ had made herself ready and was accounted righteous (cf. Revelation 19:7-8; 2Corinthians 11:2). With the destruction of Jerusalem and the Temple in 70 AD at the coming of Christ (cf. Matthew 26:64), the Jews had no divine mandate to represent God to the world. From that time forward the God of Israel was made known to the world by the Church, the Bride of Christ, alone.
The fifth blessing is pronounced upon those who have a part in the first resurrection, which is being born again or being part of a new creation (Revelation 20:6; cf. John 3:3; Ephesians 2:10), because upon this person death has no power. In 1Corinthians 15 we are told that believers are a part of a new creation. The first Adam was of the earth, but the second was from heaven (1Corinthians 15:47), and those of the flesh bear the image of the earthly, but those of the spirit bear the image of the heavenly (1Corinthians 15:49). Believers are the workmanship of God, being born of incorruptible seed, and for us all things have become new (1Peter 1:23; 2Corinthians 5:17). Death simply has no power over us (John 11:26; Revelation 2:11; 20:6).
The sixth blessing of Revelation is the fact that we can be sure that the sayings in this book are true. They aren’t just words on a page. We can have confidence in what we are told, because John testifies that he witnessed and heard them through the assistance of the angel, who was with him (Revelation 22:6; cf. 1:1). Faith is the evidence of things hoped for (Hebrews 11:1), so those who believe John will embrace what he says and be blessed (Revelation 22:7).
The final blessing is given in Revelation 22:14. It is the blessing of citizenship in the new Jerusalem come down to us from heaven (Revelation 21:1-3), which gives us the right to the Tree of Life (Christ – Colossians 3:4). We are citizens of the City of God, and we go into all the world preaching the Gospel to all nations, making disciples of them (Matthew 28:19-20) and bring them home, into the City or Tabernacle of God, for God has come down to us out of heaven to dwell with men forever.
 See Thayer’s Greek Definitions.