While there is an inseparable relationship between the Kingdom and the church, they are not to be identified. The Kingdom takes its point of departure from God, the church from human beings. The Kingdom is God’s reign and the realm in which the blessings of his reign are experienced; the church is the fellowship of those who have experienced god’s reign and entered into the enjoyment of its blessings. The Kingdom creates the church, works through the church, and is proclaimed in the world by the church. There can be no Kingdom without a church - those who have acknowledged God’s rule - and there can be no church without God’s Kingdom; but they remain two distinguishable concepts: the rule of God and the fellowship of men and women.
— Ladd, A Theology of the New Testament (p117)