Webster defines harmony as -- the combination of different musical notes played or sung at the same time to produce a pleasing sound. You can take the same notes and play them separate and you will get a melody. Should the guitar or piano be out of tune on a note in the chord, it will not be a pleasing sound. No matter how many times you play that chord over and over it will sound off. Not until the instrument has been tuned will it become a pleasing sound.
That is what Paul is talking about in Philippians when he asked them to help two ladies to live in harmony. These two ladies had let something come between them that not only were they not in harmony with each other, what had caused the separation between them had grew so big that Paul heard about it. They were singing different notes for different chords in different keys. It was so bad that they may even been singing totally different songs.
This was no little dispute that they were having. More than likely they were trying to get people to take sides. That could be why Paul said to help them live in harmony. It is obvious that living in harmony is not always possible. So what are some ways to help live in harmony?
Stay neutral - Taking sides doesn't help anyone. By staying neutral you can be useful in bringing those that are not in harmony back to at least the same song and same key.
Do not close hand when it needs to be open - The how, when, and where we worship are open handed. It doesn't matter when, how often, or what you use for communion. Likewise, the use of musical instruments in worship, all of these are open handed. The closed hand issues are that; Jesus is born of a virgin, live a sinless life, died and rose on the third day, and is the only way our sins are forgiven.
Put the others before you - By putting others before yourself you will look out for what is best for them. Showing God's love will open up the ability to bring others into living in harmony.
Put God first - This is first and foremost what will bring harmony. By leading others to what God says you have the main chord and key that the harmony is built upon.. With Jesus as the foundation all relationships can be brought into harmony.
We all need help to live in harmony with each other. By staying in tune with Jesus,we will be in key to the melody that the harmony is around. As we build our harmony around Jesus, we will become closer to each other.