How do we, as the Christian church, obtain real unity? What is real unity? Now the main Scriptural emphasis is not organizational unity. There is a unity of belief. But there is also a unity of practice. A willingness to get along with each other on the interpersonal level. And this unity of practice is rooted in the unity of belief. One of the key places the New Testament deals with unity is the book of Ephesians. It is here that the foundation is laid for the right type of unity.
The first basis of real unity is grace (Ephesians 2:1-9; 1:3-14; Colossians 2:2). This is important, because legalism, the idea we can stand before God based on what we do (Romans 3:19,20; 4:4,5; Titus 3:5,6), can produce an artificial type of unity. It does so by setting up a set of rules on what one can believe or do and then simply excludes those who do not conform. This produces an appearance of unity, but falls far short of the real personal unity that God is trying to produce (Ephesians 4:1-3; Colossians 3:12-14; Philippians 2:1-11). For legalism divides because it excludes everyone who does not think and act just the way required by it. Further, it prevents us from honestly admitting our real struggles and our real failings. And this means we end up putting on an act, which builds up walls between us and other people. Which prevents any real heart unity. Rather, it produces factions based what group we are part of (1 Corinthians 1:10-17; 3:21-23; Titus 3:10,11). The big problem in Paul’s time, and particularly at Ephesus, was the division between Jews and Gentiles (Ephesians 2:11-22; 3:1-13; Romans 15:7-13). But legalism will always find something to divide over, because it is based on performance and will look for something to show it is superior to the other person.
Now grace does not leave us where we were but transforms our lives (Ephesians 2:10; 4:20-24; 5:1-14). Therefore, real unity is not simply indulgence but is based on something solid. Grace is a positive thing based on the fact of Christ’s death on the cross (1 Peter 2:24,25; Colossians 2:13,14; 2 Corinthians 5:21). This means that it does call for some unity in basic belief (Ephesians 4:4-6; Galatians 1:8,9; Romans 16:17-20). It also requires a certain kind of behavior towards others (Ephesians 4:25-32; 5:15-21; John 17:13-26). Now the attitude that accepts everyone, no matter what, may seem the surest path to unity. But it leaves nothing to be united about. And can lead to people who are united only in name but have nothing in common. But the true unity that God wants of us grows out of grace which gives us something in common, but makes that thing not our superior goodness but that we are forgiven. For then we can be honest about who we are but still work together to change (Ephesians 4:11-16; Colossians 2:19; Hebrews 10:24,25).