Church Essentials: What Is a Healthy Church? by Mark Dever is a 6-session Bible study for adults that helps the people of your congregation understand the essential marks of a healthy church. What does it mean to be a healthy church? Church Essentials provides a framework and description of the characteristics to be incorporated into the life of a church. Whether you're a church leader or an involved member of your congregation, you can help cultivate these elements in your church, bringing it new life and health for God's glory.