The terms “Kingdom of Heaven” and “Kingdom of God” are synonymous; they represent the same thing.
“Many people think of the kingdom of God as heaven or as the church. However, the kingdom of God is not an actual physical place. A working definition of God’s kingdom from a biblical perspective can be seen as God’s universal reign as Creator and Christ’s exhaustive work as Redeemer. Since God is eternal, His kingdom is eternal. The Kingdom of God transcends time and space.”
(Source: https://www.ibelieve.com/faith/what-is-the-kingdom-of-god-10-things-christians-need-to-know.html)
Let’s see what the Bible says:
. . . and said, “Assuredly, I say to you, unless you are converted and become as little children, you will by no means enter the kingdom of heaven. (Mt 18:3 NKJV)
In order to enter the Kingdom of Heaven, one needs childlike faith and trust in the Lord. Just as earthly children trust their parents for their daily needs, we also must place our faith and trust in God the Father for daily shelter, food, protection, and all of life’s necessities.
Jesus told them another story: The kingdom of heaven is like what happens when a farmer plants a mustard seed in a field. 32 Although it is the smallest of all seeds, it grows larger than any garden plant and becomes a tree. Birds even come and nest on its branches. (Mt 13:31-32 CEV)
And he said, “With what can we compare the kingdom of God, or what parable shall we use for it? 31 It is like a grain of mustard seed, which, when sown upon the ground, is the smallest of all the seeds on earth; 32 yet when it is sown it grows up and becomes the greatest of all shrubs, and puts forth large branches, so that the birds of the air can make nests in its shade.” (Mk 4:30-32 RSV)
The Kingdom of Heaven is compared, in these Bible passages above, to a mustard seed that grows into a mighty plant whose branches become a home for birds as well as a protection from the shade for other animals.
Jesus answered, “Most assuredly, I say to you, unless one is born of water and the Spirit, he cannot enter the kingdom of God. 6 That which is born of the flesh is flesh, and that which is born of the Spirit is spirit. (Joh 3:5-6 NKJV)
The Kingdom of God is a spiritual rule over the hearts and lives of all who have become part of His kingdom by submitting to His authority, and by accepting Jesus Christ as their personal Savior and Lord.
Wherever God’s faithful people are gathered is where the Kingdom of God can be found. God will meet us wherever we gather, whenever we call upon His Name.
A relationship with Jesus Christ as our Savior and Lord is the basis of the Kingdom of God. It impacts all actions, thoughts, relationships, families, institutions, and governments. Everything on earth will come into contact with God’s Kingdom.
This Kingdom has grown all over the earth, and is still growing and overcoming all obstacles in order to touch the hearts and minds of people everywhere. Glory to God most High!