Your kingdom come. Your will be done On earth as it is in heaven.
Matthew 6:10
Jesus came to save His people from our sins (Matthew 1:21). He came to preach the gospel (Luke 4:18). And He came to establish His kingdom (Matthew 4:17).
Jesus spoke a lot about His kingdom. A lot! His parables were typically about the kingdom. When speaking to Pilate, Jesus affirmed that He is a king and that His kingdom is unlike earthly kingdoms (John 18:36). What is His kingdom like?
Some have taught that the Kingdom of God and the Kingdom of Heaven are not the same. The stronger opinion is that they are one in the same, but called by different names. I believe this second opinion is correct.
So when will (or did) Christ’s kingdom come? He established it by teaching about it, by dying and rising, and and by inaugurating the NT Church. In this sense Christ’s kingdom is now.
His kingdom has not yet been fully realized, however, since every knee has yet to bow (Philippians 2:9-11). That fullness of the kingdom will be realized when Jesus comes again.
When Jesus taught this prayer, the initial establishment was yet to take place, so at that time the prayer looked forward. We stand on the timeline between the establishment and the full realization at the Second Coming. So for us, as we await the Lord’s return in glory, we can pray this prayer both looking backward and looking forward. We look back to the establishment, praising our King. We also look forward to when His kingdom will be fully realized when our King comes again.