In practice, things are not so simple, in large part because of the law of unintended consequences. People are complex; groups of people are more so; churches, which comprise lots of highly diverse individuals and groups within them, are almost unimaginably intricate. You make a decision here, and three years later it comes back to bite you in a completely different department. You flap your wings over here, and there’s a hurricane over there a few weeks later. Church life, made up as it is of a huge number of interactions between mentally, emotionally and spiritually complex creatures, is full of unintended consequences.

Here’s a couple of highly overdrawn examples.

A local church, seized by a passion to reach unchurched children and their families with the gospel - after all, building children is easier than fixing adults - starts a series of Kidz Klubs in local council estates. It invests significant financial and volunteer resources in a relatively intensive programme over many years, with buses going out into the estates every week, regular home visits, a team of fifty people, including many teenagers, and a consistently high profile in the church at large. But over time, it is noticed that for all the good work being done, very few children and families are becoming Christians through the programme. Hundreds of children come, but few stick past the age of eleven, and of those that do, many fade away as teenagers because their families continue as they always have. As a result, after much soul-searching and with considerable sadness, it is decided to end the initiative, and redeploy the money and the volunteers elsewhere, especially into their newly attractional (and missional) Sunday meetings. The church doubles in attendance over the next five years.

But there are unintended consequences. The buses and home visiting, which in some parts of the town were the entire face of the church, stop altogether and leave many streets without any Christian contact at all. The teenage volunteers, who had been being effectively discipled in mission and service through the programme, do not experience the same levels of personal growth elsewhere. All sorts of leaders in the church, having been forced to engage on a weekly basis with the lives of people very unlike them, are able to revert to living amongst people they naturally have things in common with, and their cutting edge is softened as a result. The church as a whole had benefited from, and been emboldened by, being told monthly about the needs and challenges of entirely unchurched people, and the closure of the Kidz Klub limits the opportunities for this significantly. The net effect is that a decision made to increase the church’s missional effectiveness has various side-effects which (for a season) reduce it.

Another local church decides that, because they do not want to alienate and confuse visitors, they will discourage various charismatic practices which have, in the church’s past, been fairly typical. Speaking in languages and interpreting them are publicly prohibited; spontaneous contributions during sung worship from “the floor” are actively restricted; extended ministry times are constrained; floaty charismatic songs with incomprehensible metaphors are jettisoned in favour of gospel-centred ones; prophetic words, when they occasionally come, are described as “impressions” and only come through the accredited leaders. In other words, in the spirit of Paul’s logic in 1 Corinthians 14, those who are not Christians are protected from the potentially odder features of charismatic life.

Yet, again, there are unintended consequences. The main one is that the church as a whole, and particularly those who have been around for a few years or more, start to feel increasingly restricted and uptight in their corporate gatherings. From an environment of freedom and abandon, in which the spiritual and emotional security people experience leads to plenty of risk-taking - especially in prophecy and healing - it feels more and more like people are being evaluated, and mistakes (an inevitable part of any risk-taking culture) are no longer acceptable. Gradually, this uptightness seeps into everyday life as well: fewer and fewer people step out courageously to prophesy over, or pray for healing for, their unbelieving friends, and more and more people express scepticism about that sort of thing even happening in the first place. A few mavericks on the fringe of the church continue, but after five years of missional leadership, the mainstream has become almost entirely devoid of expectation for God to break in suddenly and powerfully in spiritual power (which, of course, also affects their enthusiasm for evangelism). Again, decisions taken to increase the church’s missional effectiveness have unwittingly reduced it.

As I say, both of these portraits are overdrawn to make a point. Things are rarely so simple; at any given time, some people are growing in their evangelistic zeal and others are shrinking, and ultimately salvation in the church is an act of God anyway. Both stories, however, would be recognisable to people in the churches in question (one in the UK and one in the US), and both illustrate the unintended consequences of going “missional”. If nothing else, they may serve as cautionary tales to those who would make mission-minded generalisations (“growing churches all find ...”, “all unbelievers hate it when ...”, and so on), and see cultural transitions within complex organisms like churches as simple. They rarely are.