The time is fulfilled and the kingdom of God is at hand.
Mark 1:15
The second petition of the Lord’s Prayer is, “your kingdom come.” The nature of the kingdom of God is one of the most discussed and debated issues related to the study of Scripture. The various views are understandable. At various times the Bible describes God’s kingdom as eternal, of having arrived in Jesus, and of still unfolding. The Bible makes it clear that God establishes His kingdom. Yet, Jesus tells us to pray for God’s kingdom to come. None of this indicates contradictions, of course. Rather, the Scriptures point to the breadth and depth of the marvelous reality of the kingdom of God.
In the most basic sense, the kingdom of God is the rule and reign of God. It is a genuine reign over a real kingdom. The kingdom encompasses both the spiritual and cosmic realms. And while the kingdom of God is eternal, established, and uncontested, our temporal perspective cannot fully behold these realities. From our perspective, God’s kingdom is slow in coming and challenged by the kingdom of this evil age.
So, while it is true that God’s kingdom is eternal and cannot be shaken (Hebrews 12:28), it is also true that we experience the kingdom within the unfolding of redemptive history. This two-fold reality is often referred to as “already / not yet.” And so we can say with Jesus that the kingdom has come and at the same time pray for the kingdom to come. When we pray for the kingdom to come we pray that the unfolding reign of God in history would be demonstrated through the purity of the church, resistance against evil, and the salvation of sinners.
The Larger Catechism is helpful in understanding what we are praying for in the second petition:
“In the second petition, which is, ‘Thy kingdom come,’ acknowledging ourselves and all mankind to be by nature under the dominion of sin and Satan, we pray, that the kingdom of sin and Satan may be destroyed, the gospel propagated throughout the world…the church furnished with all gospel-officers and ordinances, purged from corruption…and made effectual to the converting of those that are yet in their sins, and the confirming, comforting, and building up of those that are already converted: that Christ would rule in our hearts here, and hasten the time of his second coming, and our reigning with him forever…”