I am fond of using an expression I learned while I was out East: A high tide raises all the boats. I apply it in a number of contexts. The key is to make clear what the "tide" is and what the "boats" are. For instance I sometimes use it in reference to the tide being a positive attitude that a person can carry, with the boats being the people in the church.
Lately though I have been using it in a slightly different way. If you'll pardon the mixing of the metaphor, the high tide is spiritual/biblical/theological depth, while the boats are the church.
The reason for this has to do with the growth of the church I serve. Numerically we grow all the time. In 2000, our average attendance was about 80. Today it is closer to 150, and we are routinely hitting 170. God is good! What makes this growth so amazing is that most of it is conversion growth, as opposed to transfer from other churches.
Our church has a reputation of taking in people who won't be accepted in other places, people with mental illness, AIDS, and the like. We get people who are utterly unchurched. This speaks volumes about the spiritual maturity of the core of the congregation.
The problem comes in where that core has to be spread out to minister to the expanding congregation. The core gets spread out, spread thin, and, in the absence of intentional training to supplement them as leaders, burnt out. Now, we do have a process to help people grow in their social maturity. We teach them how to live in a Christian way. In some senses maybe you could argue that we help them develop spiritual maturity that way. That doesn't change the fact that they have very little knowledge about Christian doctrine. While maturity is hard to measure in that area, it is probably true that people are not, on average, that much more biblically literate than they were, say, two years ago. They might still struggle to tell you which books are in which Testament.
The net effect, as far as the metaphor is concerned, is that the core of the congregation, the ones who have the biblical and theological depth are concerned, is being let out to serve the newcomers and not being replaced. The tide is going out, so to speak.
So what do we do? Well, I am working on doctrine classes to supplement the ones that are part of our current curriculum on how to live the Christian life. After all, if we don't explain why people ought to live a certain way, and where they get the power to do it, then we are imposing a new legalism on people. The only difference is that we call it "living healthy" instead of "being righteous and holy."
And God wants more than that.