When the church in Jerusalem was born on the day of Pentecost, it rapidly became a great spiritual community comprised of many thousands and possessed all the qualities of city church life.
Its unique impact can be summarized as follows:
It was visible and could not be hidden (Matthew 5: 14-16).
It was powerful, with many signs and wonders taking place (Matthew 4: 23-25).
It had much larger resources than a local church for prayer, evangelism, operational gifts and ministries, and finances.
It provided a more suitable home base for apostles, prophets, teachers, pastors, and evangelists, one from which they went out to serve the churches in the region and beyond.
It also provided a suitable platform for visiting Ephesians 4: 11 ministries to touch the whole city effectively, in one visit.
It had the power to influence and exercise authority in secular society.
It could realistically strategize to evangelize the region, the nation, and other nations of the world.
They could exercise spiritual rule over the region and clear the heavens of the demonic powers in the heavenly realm.
BOUNDARIES OF SPIRITUAL AND NATURAL CITIES
Spiritual and natural city boundaries differ. While a significant population is necessary to provide the numbers for a city church, the physical limits of a spiritual city do not necessarily correspond with the boundaries of an actual physical one. In some of the gigantic modern cities we have today, it may work a lot better, in terms of having real relationships, to form several spiritual cities within one physical city. The practical limits of a city church are flexible and depend upon the heart, mindset, and possibly the culture and ethnicity of the people. It would depend upon their ability and willingness to maintain real, living relationships and their willingness to travel to meet regularly.
Today, in regions where there are no nearby sizable churches, a number of smaller towns and communities have successfully united together over an area of 10 to 20 miles to form an effective, functionally successful regional church. This is well established in what happened in Andrea Pradesh, India. There is no set formula for how large or small boundaries should be for a city or regional church to cover. It is dependent on the willingness of the Apostolic leaders and churches to come into one heart and mind to work together for the Kingdom.