We exist to glorify God. One way we do this is by edifying the saints. When we come together, we not only worship God but we also build up one another. God has given leaders as gifts to the church to perfect and build up believers (Ephesians 4:11—12). We also, individually, build up one another (1 Thessalonians 5:11). It is through spiritual leaders and the encouragement we give to each other that the whole body of Christ can be strengthened and matured in the faith. We do this by teaching the Bible rightly divided.
We also glorify God as His ambassadors, carrying the message of reconciliation to the world. This message is one of hope for those who are lost in their sins by declaring that those who believe fully and exclusively in the Person and work of Jesus Christ for their salvation will be given eternal life (1 Corinthians 15:1—4). See "Eternal Life" for more information.