While the smaller church grows through pastor-initiated groups and ministries, Keller states that the medium-sized church grows through multiplying these groups and by improving their quality and effectiveness. There is no room for the ‘amateurish’ approach of the small church – classes must provide a great learning experience, music must be at a certain quality, preaching must be informative and inspirational.
Once the 400 mark is reached, such a church will grow only if the habits of the 200-sized church are broken and discarded. Often it will also require that a church moves to new space and facilities.
Large church – 400-800 attenders:
With this size of church the primary circle of belonging becomes the small fellowship group – usually between 4 and 15 people in size and more of a miniature church, not focused on a particular task within church life but existing for Bible study, worship, fellowship and ministry.
In a large church the leadership qualities of tenure, skill and maturity that served smaller churches are also desirable but must be combined with commitment to the church’s distinct vision and mission. Key ministries will grow, both in size and importance, and will become an important reason visitors decide to join that church.
Staff members in a large church, including the senior leader, will find themselves in an increasingly specialised role. Preaching, vision-casting and strategising will be the senior leader’s major tasks and he must relinquish many/most of his administrative tasks or find that he has become a bottle-neck to further progress. Change and decisions now come from ‘top down’ - from staff and key lay leaders.
The means by which a large church grows differs from small and medium sized churches in that the key to its growth is what happens in the worship services – the quality and style of worship and preaching are paramount here, giving a means of growth by a front door approach. This is unlike the small church’s groups and ministries (backdoor approach) and the medium-sized church’s targeting of felt needs of constituent groups such as young families, youth, seniors, seekers - providing specifically designed ministries for them (side-door approach). For the large church the Sunday meetings provide the front door through which new people will come.