Christian thinkers have wrestled with how the Church relates to the Kingdom of God. This wrestling comes from the need to make sense of the testimony of the Gospels (which almost always refer to the “Kingdom of God”) and the letters of Paul (which refer mostly to the “Church”). Over the last two thousand years the “Church” has been emphasized far more than the Kingdom. This is most remarkable given that the Lord’s most consistent proclamation was about the “Kingdom of God” or “Kingdom of Heaven.” Thankfully many Christians, regardless of denominational background or theological heritage, are recognizing the reality of the God’s Kingdom as the rightful place of God’s rule on earth.
Historically, Christians have most frequently looked at the Church, the organization (formed by tradition) and the human persons who have formed it in any given generation, as the focal point of God’s supernatural activity on earth. This has set apart the Church from any other human gathering or association. The Church is thus a stranger in the world—for it participates (in some mysterious way) in the Kingdom of God on earth.
The Roman Catholic Church’s teaching regarding the centrality of the Church to God’s Kingdom is the most prominent example of this. For example, one of the documents produced by the Vatican II Council, Dogmatic Constitution on the Church, states that the Lord Jesus, having died on the cross and being raised to life,
“poured out on his disciples the Spirit promised by the Father (cf. Acts 2:23). Henceforward the Church, endowed with the gifts of her founder and faithfully observing his precepts of charity, humility and self-denial, receives the mission of proclaiming and establishing among all peoples the kingdom of Christ and of God, and she is, on earth, the seed and the beginning of that kingdom. While she slowly grows to maturity, the Church longs for the completed kingdom and, with all her strength, hopes and desires to be united in glory with her king.” (Cited from Vatican Council II: The Conciliar and Post Conciliar Documents, General Ed. Austin Flannery O.P. [The Liturgical Press: Revised Edition 1992], p.353; italics mine.)
Elsewhere in this document the Council clarified that in order to “carry out the will of the Father Christ inaugurated the kingdom of heaven on earth and revealed to us his mystery; by his obedience he brought about our redemption. The Church—that is, the kingdom of Christ already present in mystery—grows visibly through the power of God in the world.” (Vatican Council II, p.351)
I suppose that many Protestant Christians would not fundamentally disagree with theological assertion regarding the relation of the Church to the Kingdom. What we would dispute is how the Council narrowly defined what the “Church” is. This document asserts that the Roman Catholic Church, with its organizational structure and rites,
“is the sole Church of Christ which in the [Apostles and Nicene] Creed we profess to be one, holy, catholic and apostolic, . . . This Church, constituted and organized as a society in the present world, subsists in the Catholic Church, which is governed by the successor of Peter and by the bishops in communion with him. Nevertheless, many elements of sanctification and of truth are found outside its visible confines. Since these are gifts belonging to the Church of Christ, they are forces impelling towards Catholic unity.” (p.357)
Obviously those from Protestant traditions would emphatically disagree with the narrowing of the identification of the Kingdom of God with the organization structure of the Roman Catholic Church. This writer, for one, strongly objects that the signs and power of the Kingdom, that is, the “place” where Christ reigns on earth, should be so narrowly associated with the visible structure of any one historic self-identified “Christian” church. The Kingdom and the Church, the persons who identify themselves as disciples of the Lord Jesus, most certainly are interrelated in the invisible reality of God’s saving actions on earth (manifestation of Christ’s reign on earth). However, the Lord Jesus must not be confined to any one historical branch of orthodox Christianity; for he is Lord of all who call upon his name and follow him (see Acts 2:21; Romans 10:11-13; quoting Joel 2:32).
The grave danger for believers of any generation or any stream of Christian tradition is to forget that the Kingdom of God belongs solely to God and his Messiah—the Lord Jesus Christ. The living God does not take kindly to human presumption and pride parading itself as Christian piety. Is this not one of the main lessons from the Old Testament narratives? I write this as much for myself as for anyone. For God has made me very aware of my own tendencies toward pride and self-will. God have mercy on us all and humble us so that we can respect each other as members of the Body of Christ.