"I do not ask on behalf of these along, but for those also who believe in Me through their word; that they may all be one; even as You, Father, are in Me and I in You, that they also may be in Us, so that the world may believe that You sent Me." John 17:20 & 21
Jesus demonstrated a Unity with His Father that He wanted Christians to have with each other and with Them. When we are a Christian we are part of One Body with Christ as the head. We all have different talents and skills and backgrounds which we can use together to accomplish great things for God. If we fight, have jealousy or envy or decide that we don't feel like being a part of things then we mess up how things should be. And we make it much harder for the world to believe in Jesus Christ.
Unity in Christ's Body is something I would guess many of us need to work on. Let's Fix our eyes on Jesus, strive to love one another, focus on the truth of God's word, get rid of the pride in our own lives and learn to work together so that the world may be won!!