I truly wish that church growth would happen by simply praying and waiting upon God. While faith can accomplish anything (Mark 11:22-24), the clear commandment of Christ is to carry the gospel into all the world (Acts 1:8). When we do our part, God does His (Psalm 126:6). If you want your church to grow, you must first pray and then take decisive action, trusting that God wants souls saved even more than you do.
A good example of this paradigm is Nehemiah. He first prayed, then answered the King about his desire to rebuild the walls (Neh. 2:4-5). Later, when faced with opposition from Sanballat and Tobiah, he again prayed and then posted guards to meet the threat (Neh. 4:9). First is prayer, then action.
Two important truths here. First, prayer is not just important; it’s essential. Prayer builds faith. Prayer increases confidence. Prayer brings the supernatural into your plans. So if you want to grow, I suggest you launch a targeted prayer ministry. Target a specific area of your city. Target specific evangelism ministries. Target your God-called soul winners. Target specific unsaved people. God rarely answers general prayers (God save souls!); instead He answers specific prayers (God save Mike Smith!). When a church has a substantial percentage of its members praying and fasting for souls, it changes the very nature of the church and revival is the natural result.
Secondly, a plan of action is essential. Every church needs a clear strategy for church health and growth. They also need the leadership commitment necessary to implement that strategy. Growing churches almost always grow because they are following an intentional strategy to reach more people: lots of special events to attract first-time visitors, a well-organized guest follow-up ministry, an emphasis upon home Bible studies, training saints in the art of personal evangelism and witnessing, motivating people to witness on a regular basis, a strong small-group ministry which includes singles, youth, bus ministry, seniors and more. Faith alone will not build a church, so put some legs on your faith.