Many laws of church growth have been proposed by practitioners, sociologists and modellers. Here are several that have informed the church growth modelling project, or derived from the modelling.

Wesley’s Law of the Decay of Pure Religion

Although the principle originates with John Wesley, the founder of Methodism, it was given the status of law by Dean Kelley in “Why Conservative Churches are Growing” (page 105). His version can be summarised as: “Taking up the religion has produced benefits which makes missionary zeal too costly to engage in”. Essentially, as people grow in grace, they grow in respect and wealth, making evangelism and enthusiasm a threat to their new status. Thus, enthusiastic Christians do not stay enthusiastic for long. This law is one of the dynamic hypotheses in the limited enthusiasm model. Kelley and Wesley clearly saw that revivals burn out because of the limited period for which a Christian can remain seriously religious.

Kelley quoted Wesley’s original version of the law indirectly from Max Weber (The Protestant Ethic and the Spirit of Capitalism, chapter 5) “I fear, wherever riches have increased, the essence of religion has decreased in the same proportion. Therefore I do not see how it is possible in the nature of things for any revival of religion to continue long. For religion must necessarily produce both industry and frugality, and these cannot but produce riches. But as riches increase, so will pride, anger, and love of the world in all its branches.” Weber quotes Southey, Life of Wesley, chap. xxix. For more information, see the article on the origin of Wesley’s Law.

Kelley’s Thesis on Strictness and Strength

Strict churches are strong and more likely to grow compared with lenient churches which are weak and more likely to decline. (Dean Kelley, Why Conservative Churches are Growing and a review).

Why Conservative Churches are Growing - book cover

The thesis has proved controversial since it was proposed in the ’70s with attempts to refute and defend it. The arguments in its favour are that churches that are strict in their beliefs will offer a stronger and more desirable version of the faith. Thus they command more enthusiastic and committed support a greater desire to see others converted, and a more attractive and confident set of beliefs.

Laws from the Limited Enthusiasm Model

Diffusion Law

As a church grows the pool of potential converts shrinks and the church finds it increasingly harder to make converts due to increasing time spent on its own people, in comparison with evangelism.

Law of Limited Enthusiasm

Churches grow through enthusiasts who not only make converts but new enthusiasts. Enthusiasts only retain their potential to recruit for a limited period. Thus church growth depends on their ability to reproduce themselves.

Law of Revival Growth

If the ability of enthusiasts to reproduce themselves is above a threshold depending on the losses from the church and the number of potential converts, then rapid revival growth in the church will occur.

Law of Extinction

If the ability of enthusiasts to reproduce themselves is below a threshold depending on the losses from the church, then a church will not sustain itself at any level but become extinct.

Law of Growing Populations

In a growing population, the thresholds of extinction and revival growth are lowered. Thus church survival and revival growth are more likely in a growing population.

Law of Renewal

If a church makes enthusiasts by renewing existing believers, revival growth can be achieved even if the church is otherwise not converting sufficient people, providing there are critical masses of enthusiasts and church numbers.

Law of Spiritual Life

Believers can enhance their spiritual life by engaging in corporate spiritual activity leading to them being more effective in conversion. Attending worship, prayer meetings and Bible study can be beneficial! Hardly rocket science, but a much-neglected law!

Church Growth Laws from Sociology of Religion

Olson’s Law of Church Friendships – The “Club” Effect

As churches grow, so does the quality of the friendships in the church, thus making it harder for new people to join and integrate. The desire to benefit from existing friendships exceeds the cost required to recruit new people. (Due to Daniel Olson, Church Friendships, Boom or Bust?)

Secularisation Hypothesis

As society progresses, religion loses its authority in all aspects of social life and governance. This hypothesis has been interpreted in several ways:

  1. A rise in economic development and wealth leads to a decline in the demand for religion;
  2. A rise in education and knowledge leads to a decline in the demand for religion.

These statements are not the same. The first implies wealth is a competitor for time, and the second that religion is for those who have a limited view of reality. Different people interpret “progress” in different ways: wealth, economic development, science, education, political and social freedom.

Principle of Inappropriate Supply

Churches can decline due to their failure to supply the spiritual needs of society rather than there being any lack of spiritual demand in society. (Stark and Iannaccone). This principle was proposed to counter the secularisation hypothesis. The decline of religion’s role in society is not the same as a decline in demand. Its role could decline due to the religion being unable, or unwilling, to meet the demand, as well as other reasons.

Laws Drawn From Other Disciplines

Michels’ Iron Law of Oligarchy

As organisations grow and mature, they develop oligarchies due to the tendency of leaders to organise the structure to consolidate their interests. This approach makes it harder for people to get involved, leading to less enthusiasm and lower recruitment and retention. This principle was proposed by sociologist Robert Michels in his book “Political Parties”. Limits-to-growth were secondary to his concerns. However, political scientists have used this law as one explanation for the failure of political parties to keep growing. For churches, this could be expressed in their tendencies to develop into different classes of priests and laity, making it harder to recruit, involve and retain the laity.

Olson’s Law of Free Riding

The larger an organisation grows, the higher the opportunity for free-riding by people who benefit from the organisation but do not contribute. This effect makes it harder for the organisation to grow as more resources need are diverted to benefit the free-riders with fewer resources available for recruitment. The law is stated by Mancur Olson in “The Logic of Collective Action”. He applied it to general organisations of people, and it has been used by political scientists as another reason for the difficulty political parties have in growing. For church growth, it would mean that larger churches have a higher proportion of people who benefit without contributing, thus slowing their growth.

Law of Organisational Complexity

As churches grow in numbers, the networks of people, and physical resources, become more complex, diverting time from evangelism and recruitment, towards maintenance. This law is not about free-riding but about the increasing demands of larger churches leaving less time for evangelism. The effects of complexity can be reduced by good organisation and delegation on the part of the church (see below). There is a reverse effect that as a church declines, but its physical plant stays the same, the dwindling number of members have to devote more of their time to the physical resource and thus less time for evangelism.

Tan’s Law of Positive Complexity

If an organisation can respond to its growth by creating efficient structures to mobilise its people, its growth can be enhanced due to the provision of specialist benefits not available in smaller organisations. This effect can counter the impact of free-riding and organisational complexity. It was proposed by Alexander Tan, a political scientist (1998), who examined empirical evidence from political parties. In church terms, this law implies that big churches can provide more benefits than smaller ones and thus be more attractive and hence recruit and retain more people.

Miscellaneous Laws of Church Growth

Wimber’s Law of Friends

“People who join a church stay there mainly because they make friends”. Often said by John Wimber, founder of the Vineyard Church, after his experience as a church growth consultant. He probably did not originate the expression but did much to popularise it.

Law of Volunteers

“Church is a voluntary society, no one has to go!” Churches often make decisions that alienate members, such as poor quality worship service, changes in doctrine, or revision of moral codes. It can easily be assumed that members will remain loyal come what may. In reality, they are free to leave and go to another church or even give up on Christianity altogether. The law can also apply when circumstances outside the church change, tempting, or forcing, members away from the church.

As far as I know, the law has no specific statement in academia. However, it was frequently quoted by a friend of mine, especially when his church did things that upset people in the congregation! It does indicate that church leaders should make decisions that take the loyalty of members for granted.

God Has No Grandchildren

When someone is converted, born again, they become a child of God. This is the only way to have a personal relationship with God. Whatever the blessings of being brought up in a Christian family, and there are many, such a person cannot acquire that personal relationship from their parents. They need to be “born again” themselves. True religion cannot be secondhand.

When translated into a law of church growth, it means that for the church of true believers to grow then at the minimum their children must be converted. If not, the temptation is to allow them to join the church without conversion. Such a church is considerably weakened as it contains a growing number of people who are not converted. In later generations, the children do not even stay in the church as it has little living faith to distinguish it from the outside world. With few conversions and insufficient generational transmission, the church steadily declines until it is extinct. Sadly, it is a law seen in action in many churches in the West.

Principle of Divine Revelation

Also known as the principle to restore your sanity after all the other church growth laws! “Truth cannot be determined by reason and experiment alone, it requires divine revelation and faith”. That revelation is the Bible. In the words of Billy Graham: “The Bible says….”