In Revelation 1:1 John specifically states that the prophecies of Revelation would begin to take place in a very short time. It will a sincere heart to read the contents of the book and only hope for truth.
“The Revelation of Jesus Christ, which God gave Him to show to His bond-servants, the things which must soon take place; and He sent and communicated it by His angel to His bond-servant John, (Revelation 1:1 NASB)
He emphasized this truth in a variety of ways through Prophetic and Apocalyptic language. There are 3 words to indicate the imminence of events in the book of Revelation.
The first Greek word translated “soon” in Revelation 1:1 is from the Greek word tachos. According to Arndt and Gingich Lexicon, tachos is used in the LXX and certain non-canonical writings to mean speed, quickness, swiftness, haste. John uses the same word in Revelation 2:16; 3:11; 22:6,7,12,20.
Secondly John also uses the Greek word “eggus”:
“Blessed is he who reads and those who hear the words of the prophecy, and heed the things which are written in it; for the time is near.” (Revelation 1:3 NASB)
The word which is translated here as “near” it is also used in Revelation 22:10. This term speaks of temporal nearness and John uses it to indicate the imminence of those events in their time.
The third Greek word is mello; it is translated “about to”’ in Revelation 1:19 & 3:10.
“Therefore write the things which you have seen, and the things which are, and the things which will take place after these things.” (Revelation 1:19 NASB)
The phrase, “the things which will take place after these things” is literally “the things which are about to occur” and in 3:10,
“which shall come upon all the world” is literally “is about to come upon the whole world [oikoumene].” If we apply the principle of audience relevance, what would the original readers have thought when they read this? [oikoumene] refers to the civilized world of their time which comprised of the entire stretch of the Roman colony. Surely they would not have taught of the year 2015, America and blood moons.
John strategically places these words at the introduction and conclusion of the book. John was telling the seven churches to expect these things at any moment and not 2,000 years. If it was for fulfillment 2,000 years later why bother to write a letter to the 7 churches going tribulation with him. That would have in no way serve as an encouragement in those turbulent times. And Surely it will not serve as an encouragement to prophesy its fulfillment in our time too.
There are several reasons to justify the reason why this book was written to the 2 churches, chiefly which was to let them know that in their trying moments, light was at the end of the tunnel and that their redemption was drawing near.