The Ekklesia that Jesus founded is essentially spiritual in nature, and because it is spiritual, it is heavenly. If you can understand this it will answer a lot of the questions and settle a lot of issues that arise when we try to naturalize it, bring it down to the earth, and make it all about the “meeting” or the “building” or the “organization”.
The Ekklesia is the spiritual assembly of those who have been called out of one spiritual place (the kingdom of darkness) and into another spiritual place (the Kingdom of Heaven, also known as the Kingdom of God and the Kingdom of Light).
In Matthew 16:18, Jesus said “I will build my church” (KJV).
Matthew 16:18 And I say also unto thee, That thou art Peter, and upon this rock I will build my church;
and the gates of hell shall not prevail against it.
Easton’s Greek Dictionary informs us that the word “church” is derived from kuriakon which literally means “the Lord’s house”, from kurios, “lord”). It was used by ancient authors for the place of worship, the building in which the congregation worshiped.
Easton further informs us that the Greek word translated “church” is ekklesia, which is synonymous with the word kahal in the Old Testament. Both words mean simply “assembly”, the nature of which is determined from the context in which the word is found. There is no clear instance of it being used for a place of meeting or worship, though in post-apostolic times it early received this meaning.
Nowhere is ekklesia used to mean the Christian inhabitants of a country, as in “Church of England”, “Church of Scotland”, etc.
Thus Jesus promised to build an unshakable assembly which the authorities of hell would not be able to withstand or prevail against (gates of a city were where the authorities assembled).
I want to stress that when we use the word Church in this site, it refers to the spiritual assembly founded by Jesus, unless otherwise specified.