The Kingdom of God is the creating and ruling Family of God soon to administer the government of God on earth. Though the Kingdom of God does not now rule the earth, those who have God's Spirit are under its rule in their lives. When Jesus Christ returns, He will reestablish its rule on earth, and the saints, resurrected as spirit kings and priests, will reign with Him for a thousand years. Following the second death and the Lake of Fire, the Kingdom will be completely fulfilled when God the Father descends from heaven to rule for all eternity from New Jerusalem.
Scripture References:
Daniel 2:44; Isaiah 2:2-4; 11:1-10; Micah 4:1-4; Mark 4:11; John 3:3-7; I Corinthians 15:50-54; Colossians 1:13; Hebrews 11:13-16; Matthew 25:31; 20:21; Revelation 2:26; 5:10; 19:16; 20:4-6, 12-15; 21:1
From the Library: Kingdom of God
Why Such Confusion About the Kingdom of God?
Sermonette by Craig SablichIn Matthew 6:33, Jesus states that seeking His Kingdom is our primary goal. Most Christian organizations have no concept of what the Kingdom of God is.
The Kingdom of God
Feast of Tabernacles Sermon by Richard T. RitenbaughThe Kingdom of God includes a King, territory, citizenry, and laws. The term kingdom (Greek basileia), has a past, present and future application.
Is the Kingdom of God Within You?
'Ready Answer' by Richard T. RitenbaughWhat did Christ mean by 'the kingdom of God is within you'? This statement has tripped up students for centuries, but the context makes it is very plain.

God's Kingdom in the Parables (Part One): Sower and Seed
'Prophecy Watch' by David C. GrabbeThe 'kingdom of heaven' is commonly interpreted to describe the church, but in the first four parables of Matthew 13, it has a clearer application: Israel.
How Much Do You Value the Kingdom of God?
Feast of Tabernacles Sermon by Martin G. CollinsMartyrdom is not a penalty because a person has failed to qualify for the Place of Safety; rather, it is a badge of honor for those who have overcome.

God's Kingdom in the Parables (Part Four): The Pearl, the Dragnet, and the Householder
'Prophecy Watch' by David C. GrabbeJesus' parables of the Pearl of Great Price, the Dragnet, and the Householder resolve the problems raised in their corresponding earlier parables.

The Model Prayer (Part Four): Your Kingdom Come
Bible Study by Richard T. RitenbaughJesus instructs His disciples to ask God to establish His Kingdom. By doing so, the supplicant aligns himself with God's plan for humanity.
Thy Kingdom Come
Sermonette by Ronny H. GrahamMost professing Christians hold to the pagan belief that heaven is the reward of the saved, imagining that they will waft off to heaven at death.
For more resources, please see the library topic for Kingdom of God