Unhealthy churches cause few problems for the healthiest Christians; but they are cruel taxes on the growth of the youngest and weakest Christians. They prey on those who don’t understand Scripture well. They mislead spiritual children. They even take the curious hopes of non-Christians that there might be another way to live, and seem to deny it. Bad churches are terribly effective antimissionary forces. I deeply lament sin in my own life, and sin’s corporate magnification in the life of so many churches. They seem to make Jesus out to be a liar when he promised life to the full (John 10:10).
Mark Dever, Preface to the Second Edition, Nine Marks of a Healthy Church, (Crossway, 2013), 17.