It was C. Norman Kraus who said, “The life of the church is its witness. The witness of the church is its life. The question of authentic witness is the question of authentic community” . Our unity and love for one another as followers of Jesus is a proof to the world that the heavenly Father sent Jesus to earth. Jesus prayed for his future disciples that “they would be brought to complete unity to let the world know that you sent me” (John 17:23). Our unity is a proclamation of the gospel.
When the world sees our unity, it resonates with their innermost being because man was created not to live a detached existence, but rather to belong. Our unity may even make the world uncomfortable as it exposes their disconnection with others and with God.
Unity is at the heart of making disciples because it is rooted in the nature of God. Jesus came to earth to introduce the kingdom of God through demonstrating the unity he had with his own father. He said, “Anyone who has seen me has seen the Father. How can you say, ‘Show us the Father’? Don’t you believe that I am in the Father, and that the Father is in me?” (John 14:9-10). But he also worked for nearly three years to cultivate unity among his followers knowing that their relationships with one another would be a picture of the gospel to the world. He confronted anything that could cause disunity (e.g., arguing among themselves who was the greatest, Mark 9:33-34) and encouraged anything that would build unity. (“Love one another as I have loved you.” John 13:34-35)
Kevin (not his real name) was an atheist who had become friends with our group of disciples. Kevin later became a follower of Jesus and told us that the group’s love for each other was something that he had longed for his whole life. He had never had a place to belong. This love caused Kevin to re-investigate the very claims of Christianity that he had been earlier refuting.
Some closing thoughts:
- Be intentional in building unity among your disciples. Talk to your disciples about unity. I have worked on 4 church staffs and 2 para-church organizations and do not recall ever having a deliberate plan to cultivate unity among the believers.
- Believers love for one another and unity as disciples may be one of the best ways to reach atheists.
- Making disciples should be done in a community (as Jesus demonstrated both with the twelve disciples and the other disciples in his home town of Capernaum.) It is in the interpersonal relationships among the group that love is learned and demonstrated.
 C. Norman Kraus, The Authentic Witness: Credibility and Authority (Grand Rapids: Eerdmans, 1978), 156.