think the most important thing I could say about the kingdom of God that would help people make sense out of all the uses is that the basic meaning of the word kingdom in the Bible is God’s reign — R-E-I-G-N — not realm or people. The kingdom creates a realm, the kingdom creates a people, but the kingdom of God is not synonymous with its realm or its people.

“God decided the kingdom of God would be most gloriously revealed in a crucified and risen king.”
Psalms 103:19: “The Lord has established his throne in the heavens, and his kingdom rules over all.” You can hear the basic meaning of the word kingdom as rule. It doesn’t mean that his kingdom rules over his realm; it means that God’s reign or rule governs all things.

He sits as king on his throne of the universe, and his kingly rule — his kingdom and his reign — governs all things. The basic meaning of the word kingdom in the Bible is God’s kingly rule — his reign, his action, his lordship, his sovereign governance