Broadly speaking, the kingdom of God is the rule of an eternal, sovereign God over all the universe, Monarch of all creation.
For the Lord Most High is awesome, the great King over all the earth.
Psalm 47:2 NIV
For the Lord is the great God,
the great King above all gods.
Psalm 95: 3 NIV
More narrowly, the kingdom of God is a spiritual rule over the hearts and lives of those who willingly submit to God’s authority.
Hear my cry for help, my King and my God, for to you I pray.
Psalm 5:2 NIV
The Lord sits enthroned over the flood;
the Lord is enthroned as King forever.
The Lord gives strength to his people;
the Lord blesses his people with peace.
Psalm 29: 10-11 NIV
“I’m fairly convinced that the Kingdom of God is for the broken-hearted. You write of ‘powerlessness.’ Join the club, we are not in control. God is.”
Fred Rogers
“If Jesus is king in heaven then the Kingdom of God is in heaven. If Jesus is king, reigning on earth, then the Kingdom of Heaven is on earth. If Jesus is king in my heart, then the Kingdom of God is in me.” Rick Warren
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“The Lord is my King,” my allegiance I owe.
I’ll faithfully travel where He bids me go.
‘Til homeward I turn at the setting of sun,
To hear my Lord saying, “Dear servant, well done.”