Let me start by demonstrating what happens when discipleship is not prioritized. Looking back over the last several decades of church history, we can see the effects of the church-growth movement together with the seeker-sensitive (and seeker-driven) movement. These did help churches come to grips with some of the cultural changes in our communities and some of the abiblical aspect of our traditional approaches to ministries. Nevertheless, many churches found themselves overly focused on the corporate service and the attainment of attendance goals. Numerical growth could be counted, but authentic growth is hard to observe and can never be reduced to numbers. As churches pursued this goal, they often began to see the church service as ‘the’ light into the world and often forgot the importance of leading God’s people to be lights unto the world. Christians would come to the church service and receive at best another presentation of the gospel and at worst a self-help gospel. Either way, the converted believers failed to receive sound instruction in the Word beyond spiritual milk. In their drive to evangelize the lost, pastors (the mature and gifted teacher of the Word) often failed to feed the sheep properly. In time, many church leadership teams (pastor, staff, etc.) chose to pursue a more corporate form of leadership and relationships to the congregation as a whole suffered.
So, how does a properly functioning, biblically faithful discipleship ministry impact the future of the church. The short answer is the same way as it did in the Bible. Real Christians will be engaged by faithful God-called teachers (like Paul), they will come together and grow in fellowship (like all the churches mentioned in Scripture), they will make mistakes and need correction by each other and the leaders (just like in Scripture), and they will be led of God and encouraged by each other to maintain faithfulness to God, grow in commitment to His word, and remain active in their witness (just like in Scripture).
Such a ministry will create members that are sound in their theology. They will be enabled to “demolish arguments and every pretension that sets itself up against the knowledge of God, and” “take captive every thought to make it obedient to Christ” (2 Cor 10:5). They will be able to encounter the culture at large and remain steadfast in their faith. They will draw closer to God and to one another as they “put to death … whatever belongs to the earthly nature” (Col 3:5) and “take up their cross (Matt 16:24) instead of giving way to mere sentiment. As opposed to giving themselves over to the egocentrism which has become so pervasive, they will become God-centric and learn to “seek first his kingdom and his righteousness” (Matt 6:5).