Why is it important for Jesus’ church to remain unified? What happens when the church stops being “one” (see Ephesians 4:4-6)?

Jesus gave two key marks of his church: love and unity. About love, he said, “A new command I give you: Love one another. As I have loved you, so you must love one another. By this everyone will know that you are my disciples, if you love one another” (John 13:34-35). On unity, he prayed to his Father that the church be united “so that the world may believe that you have sent me” and that you “love them even as you love me” (John 17:19, 23). According to Jesus, these are two necessary marks of a true church that follows him: love for one another and unity with one another. Without love, the world will not know that we belong to Jesus. Without unity, the world will not know that Jesus came from God the Father and that the church is loved by God. Sad, but true is the fact that many choose not to believe in Jesus because of the division they see among those claiming to follow Christ.

Divisions in the church not only harm the church’s witness to the world, they also destroy the peace, joy and fellowship of the church and may even destroy the church itself. Controversies, quarrels, heresies and disputes promote spiritual strife as members turn against each other (Galatians 5:15). They “become conceited and provoke and envy one another” (5:26). Paul condemns “hatred, discord, jealousy, fits of rage, selfish ambition, dissensions, factions and envy” as “works of the flesh.” “Those who live like this will not inherit the kingdom of God” (5:20-21).

When the church stops being one, it dishonors Christ, ruins its witness to the world, and robs itself of joy and peace. A divided, conflicted church is self-destructive. Jesus said, “Every kingdom divided against itself is laid waste, and a divided household falls” (Luke 11:17).