Christian unity has been on the religious agenda for the past several decades and the question being asked is this: "How can all the churches be one, thereby presenting a united body to an unbelieving world?" The aspiration is honourable and noble, but unity must be grounded in what the Bible teaches.

Some churches are willing to settle for the lowest common denominator in their pursuit of unity. Among these churches a variety of conflicting beliefs exist and, in some cases, even some of the fundamentals of the Christian faith are denied. The efforts of these churches will not produce the unity Jesus prayed about – "I pray also for those who will believe in me through their [the apostles'] message, that they all may be one... so that the world may believe that you have sent me." (John 17:20-21) What these churches will succeed in doing is producing union, not unity, and there is a difference. I will explain this by way of an illustration. A company of soldiers in an army may be the best unit in the forces: well trained, efficient, disciplined, etc. - a model unit. However, these soldiers may hate their commanding officer and dislike each other. Their views on politics, religion and family values may not be remotely similar. They have little in common. Let's apply this to church unity. You cannot have unity when there is disagreement on fundamentals such as the authority of the Bible in all matters of faith and practice, forgiveness of sins through faith in the atoning sacrifice of God's Lamb, baptism in the saviour's name and belief in his bodily resurrection. There must be agreement on these gospel truths. Biblical unity between those whom the Lord has saved and those who have not been "born again of water and the Spirit" (John 3:5) is impossible.

The meaning of biblical unity is found in Paul's letter to the saints at Ephesus. He says, "Make every effort to keep the unity of the Spirit through the bond of peace." (Ephesians 4:3) This is a most illuminating verse of Scripture. We are not responsible for creating unity, but we are responsible for maintaining unity in the church that has been created by the Spirit. Biblical unity is the work of the Holy Spirit and exists only among those who are redeemed. It is called "the unity of the Spirit" because it is made possible through the Spirit's ministry when it convicts us of our sin, enlightens our understanding and baptises us into Christ. (John 16:8; Acts 2:37; Hebrews 6:4; 1 Corinthians 12:13) The Spirit joins us together in one body – the church of Christ - which embraces all the redeemed. And the total number of the redeemed is known only to God: "The Lord knows those who are his." (2 Timothy 2:19) Therefore, we must not think that our church directory is a copy of the Lamb's book of life. God's people are scattered all over the world, but we have this in common with each other: "[We] are all sons of God through faith in Christ Jesus, for all of you who were baptised into Christ have clothed yourselves with Christ... you are all one in Christ Jesus." (Galatians 3:26-28)

That the church is both local and universal is expressed in Paul's remarks to the Corinthians: "To the church of God in Corinth [that is, the local church]... together with all those everywhere [that is, the universal church], who call upon the name of our Lord Jesus Christ – their Lord and ours." (1 Corinthians 1:2) At the time Paul wrote, the people of God were to be found in Corinth, Jerusalem, Ephesus, Philippi, Rome, etc.. They were separated by distance, by culture and by race, yet they were all united together in one body – the church, which Jesus bought with his own blood. (Acts 20:28) Many of them did not know each other, but the important thing is that they all knew the Lord Jesus Christ and that is what united them together as the church of Christ.

Joining hands in a gesture of Christian unity with those who do not endorse an evangelical faith sends the wrong signal to an unbelieving world, resulting in further confusion. For unity can only exist among those who have been converted to the Lord Jesus Christ.