Often I see men speak of the coming kingdom as though the church’s kingdom is a heavenly one and Israel’s will be earthly. Some even say that there is no earthly kingdom. I must ask if there is not a more substantive difference between the kingdom of heaven which is already in existence   (Matt 16:28), and a future earthly kingdom that Jesus seems to have taught in the prayer that we refer to as the Lord’s Prayer? Jesus also confirms that He will one day be an earthly king in His conversation with Pilate. Old Testament Scriptures actually Prophecy such an earthly kingdom, and many yet unfulfilled earthly events which Messiah would perform. Peter refers to this event in his second sermon when quoting about Messiah in Acts 3

Acts 3:18-21 But the things which God announced beforehand by the mouth of all the prophets, that His Christ would suffer, He has thus fulfilled. Therefore repent and return, so that your sins may be wiped away, in order that times of refreshing may come from the presence of the Lord; and that He may send Jesus, the Christ appointed for you, whom heaven must receive until the period of restoration of all things about which God spoke by the mouth of His holy prophets from ancient time.
There are at least two ways to view the coming earthly kingdom. Some view it as a time when the church reigns over the earth with Christ the king, and when the promises to Israel of an earthly kingdom in which Israel is exalted will take place. I see it as the time when the one new man comprised of All saints will occupy the land and receive all the promises.
Somehow although there is a present and, of course, future heavenly kingdom of which we are definitely a part right now; it would be very difficult to conclude that our kingdom is only heavenly. We are according to Paul in Eph.2 to receive the covenants and promises that before coming to Messiah we were outside looking in on.
In the Acts 3 passage recorded above we hear it seems that heaven has received Jesus until the Jews repent, Peter was speaking to the men of Israel; and also recorded there we hear that then all things are fulfilled spoken by the prophets.
If our kingdom is only heavenly, then how do we rule with Christ who is at that time the King of Israel?
If our kingdom is only heavenly, then how do we participate in the promises and covenants with the commonwealth of Israel (read Eph 2) many of which are earthly.
If our kingdom is only heavenly how do we become one new man?