That they all may be one, as You, Father, are in Me, and I in You; that they also may be one in Us, that the world may believe that You sent Me. John 17:21
God often speaks of human relationships as a part of His mission to redeem a lost world (John 13:20; Matt. 25:40). One reason He gives for a husband and wife to live in unity is so they can produce a “godly seed,” that is, children who love and obey God, who can be used in God’s mission to bring redemption to a lost world (Mal. 2:14-15). Similarly, the church is the body of Christ. A church cannot be on mission with the Father in our world if its members are waging war with one another (1 Cor. 12:12). There is a crucial connection between our relationships with others and the salvation of those around us.
We might assume that during Jesus’ prayer before His crucifixion, He would have prayed that His disciples would have courage, or would remain faithful, or would remember what they had been taught. Yet He asked that His followers would remain united in their love for one another. Jesus understood that it is spiritually impossible to love God but not love others.
A test of your love for God is to examine your love for others. Our tendency is to say, “Heavenly Father, the problem is not between You and me. I love You with all my heart. I just don’t love my brother.” And God says, “That is an impossibility. You cannot love Me without loving the ones for whom My Son died” (John 13:34-35). Your life will not convince those around you of the reality of Jesus if you cannot live in unity with your fellow Christians.