A now elderly John, who was one of Jesus' closest confidants, was serving time in the Roman penal colony of Patmos - off the coast of modern day Turkey. It is here that he receives the revelation of Jesus Christ.

Most will tend to compartmentalize this prophecy. But remember, Jesus told John in several places to write down the whole prophecy "and send it to the seven churches" (Rev 1:11). The intended audience is the churches. This is confirmed at the end of the prophecy when Jesus states very plainly:

“I, Jesus, have sent My angel to give you this testimony for the churches. I am the Root and the Offspring of David, the bright Morning Star.” - Rev 22:16

John begins this letter to the churches by stating:

Grace and peace to you from Him who is and was and is to come, and from the seven Spirits before His throne, and from Jesus Christ, the faithful witness, the firstborn from the dead, and the ruler of the kings of the earth

And then note this statement about the activity of Jesus:

To Him who loves us and has released us from our sins by His blood, who has made us to be a kingdom, priests to His God and Father—to Him be the glory and power forever and ever! Amen.

First, by releasing us from our sins by His blood, He has made us to be a kingdom, priests to His God and Father.

So the kingdom making process has started. But it's not here yet in its fullness. For John states:

Behold, He is coming with the clouds, and every eye will see Him—even those who pierced Him. And all the tribes of the earth will mourn because of Him. So shall it be! Amen.

It's in the midst of trial and tribulation that the process of kingdom making begins. Note the tone and content of each of the statements given to each of the seven churches. The message is one of overcoming - till the end. In every single case. Even to the weak church at Laodicea Jesus states:

To the one who overcomes, I will grant the right to sit with Me on My throne, just as I overcame and sat down with My Father on His throne. - Rev 3:21

Later, while John is describing the throne room in heaven, we see four living creatures and the twenty-four elders singing a new song.

“Worthy are You to take the scroll and open its seals,
     because You were slain,
and by Your blood You purchased for God
     those from every tribe and tongue and people and nation
You have made them to be a kingdom
     and priests to serve our God,
     and they will reign upon the earth.

So, our future destiny is to reign upon the earth. But in the interim, we will have trouble. Note that it's after this song that Jesus begins to break the seals on the scroll that releases conditions on the earth that are far from ideal. But they are a preparation for what is coming. It's a process that culminates in justice.

It's the outcome we are to focus on. I believe it is that outcome that Jesus was describing when He gave His famous "Sermon on the Mount".