According to Ephesians 4:3 unity is linked directly with the Holy Spirit.  There is a "unity of the Spirit."  It seems safe to say that the person who is filled with the Holy Spirit will be a uniter and not a divider.  It certainly must grieve the Holy Spirit when the person He indwells is given to pulling people apart instead of bringing them together.   The devil is a deceiver, devourer and divider.  He is probably the author of the strategy that says "divide and conquer."  He is an unholy spirit.  The Holy Spirit is a uniter who pulls people together around the Lord Jesus Christ and His truth. 

Many have been the excuses given for division among God's people.  A church is to be a group of united people.  The Holy Spirit is always pulling people in a church toward unity in Jesus.  It is the result of His nature.  He does it to the degree we cooperate with Him and let Him have His way.  He does it unless we prevent Him from doing it.

Unity is a spiritual quality.  It is something inside of people.  It is a way of thinking.  It is not the same as uniformity.  Uniformity has to do with external arrangements.  It can be forced.  Unity cannot.  Unity and maturity go together.  Children often quarrel and separate.  Immature adults do the same and reveal their failure to grow up, emotionally and spiritually.  Paul appealed to the people in the Corinthian church to "agree with one another."  He wanted them, at the direction of the Holy Spirit, to live with no divisions so they might be perfectly united in mind and thought." – I Corinthians 1:10.  He goes on to say that he could not communicate with them as adults but as infants since there was jealousy and quarreling among them.  God's plan for each of His children is to bring them to maturity in Christ.  For that to happen there must be the developing of a spirit of unity – Romans 15:5.  A refusal to let the Holy Spirit develop that spirit in us is a refusal to grow up.  It is possible for us to be chronological adults but still be baby Christians.

There is a great amount of material in the Bible on unity.  That is no doubt because of the nature of God.  He is a trinity – a tri-unity.  Jesus prayed to the Father that He would protect the disciples by the power of His name after he went back to heaven so that they would be one as He and the Father were one – John 17:11.  He went on to say in the same prayer that He had given the disciples the glory that had been given Him so that they might be one as He and the Father were one – John 17:22. The church was to reflect the beauty of God to an ugly world and that beauty came out of the unity of the Godhead.  What a provision for the people of God!  And it is still available through the person and ministry of the Holy Spirit.  In fact, as stated in Ephesians 4:3 it doesn't have to be produced or created it only has to be kept or maintained.

It hasn't been and won't be maintained apart from the life and ministry of the Holy Spirit.  Not only do we have the enemy, the devil, dividing to conquer, we each have a sinful human nature which is divisive in character.  There is a work of the Holy Spirit that enables us to put to death the deeds of our sinful nature and live in a way that is holy and pleasing to God.  When we do, the unity of the Spirit will be preserved.  When we don't, it will be lost.  Church history is a story of lost unity and yet the Church continues and grows because of the Holy Spirit pulling people together.  When that whole story is unfolded at the Judgment Seat of Christ there will be many lost reward because of unholy separations.  The picture will no doubt be painted of the opportunities each of us had to put our sinful nature to death and follow the Holy Spirit in building unity.  Perhaps that is one reason God will have to wipe the tears from our eyes as we see what could have been.  There will also be many rewards for people who have contributed unity as they were enabled by the Holy Spirit.

The Holy Spirit leads us in unity by continually taking us to Jesus and revealing the things of Jesus to us. Paul's desire for the Romans who loved God was that they would have this unity, provided by the Holy Spirit, as they followed Christ Jesus.  He wrote to the Philippians believers about being united with Christ and said that the fellowship of the Holy Spirit made it possible for them to be like-minded, have the same love and be one in spirit and purpose – Philippians 2:1-2.  It all flows out of the person and work of Jesus.  There is one Lord and from Him one faith, one body, and one baptism.  Jesus came to reveal one God and Father of all who is over all and through all and in all.

The loss of unity can be attributed to the desires of the sinful nature replacing the directions of the Holy Spirit. He will lead us to the same attitude that Jesus had when He made Himself nothing and became obedient to death on the cross.  The opposite of that mindset is one of competition and comparison.  The culture in which we live is built on this way of thinking.  Competition is the foundation on which much of our culture operates.  We are instructed to turn away from envy, jealousy and suspicion.  Selfish ambition is the opposite of Jesus' example.  In II Corinthians 12 there is a list of unity destroying behaviors: quarreling, jealousy, outbursts of anger, faction, slander, gossip, arrogance and disorder.  All of these are a denial of grace.  Grace teaches us that we are all needy people who cannot presume to be better than someone else.  Abusing other people indicates that we are living under the control of the sinful nature rather than the Holy Spirit.

There are times when an apparent unity must be exposed.  John wrote that people broke unity and went out from the community of believers because they were not really united with them – I John 2:19.  Paul said that there had to be division so that the authentic would be apparent – I Corinthians 11:19.  The essentials of the gospel must be held to tenaciously and separation from those who deny or depart from them will be necessary.  The peripheral issues should not be allowed to tear God's people apart.

The unity of the Spirit is described in Psalm 133 as something beautiful.  It reflects the  splendor and radiance of God.  Unity makes God's people beautiful and is one of the great results of being filled with Spirit of glory and grace!