God is all about oneness. When a man and woman marry, they become one flesh. Jesus said that He and the Father were one. And we His Church are to be united as one as well. We are to make every effort to keep that unity. That means that it takes effort to keep that unity. The word translated here ‘keep’, tereo in the Greek, means to guard from loss or injury, to take care of, to attend to carefully, to preserve. We are to be on guard against anything that might cause division. We are to take great care in protecting the body of Christ and the oneness that we share in the Spirit.
For there is one body, the Church, and we are all part of that same body. When one part suffers or is attacked, or ridiculed, we all feel the effects. For there is one Spirit, the third person of the Trinity, that dwells in our hearts, comforts us in distress, teaches us spiritual things, and empowers us to accomplish God’s will for our lives. For there is one hope, salvation through Christ, that we share, that anchors our soul. For there is one Lord, Jesus Christ, that bled and died for all mankind and sits enthroned as our King. For there is one faith, the Gospel message, by which we are saved. For there is one baptism, into Christ, by which we die to our sinful nature and are raised to new life in Him. And there is one God and Father of all, who has always been and always will be.
God cares about oneness. The mystery of the Trinity is three in one. We are to show the world the mystery of God’s perfect peace that can make one out of many. The only way the Church can do this is by remaining in oneness with Christ.