"Agree with each other. Don't be proud. Be willing to be a friend of people who aren't considered important. Don't think that you are better than others." Romans 12:16
Humility is about the only way to preserve harmony. So, if you value harmony you must place a high priority on humility.
What is humility and how does it happen?
If you want to understand what it means to be humble there is not better example that this:
"Don't do anything only to get ahead. Don't do it because you are proud. Instead, be free of pride. Think of others as better than yourselves. None of you should look out just for your own good. You should also look out for the good of others. You should think in the same way Christ Jesus does. In his very nature he was God. But he did not think that being equal with God was something he should hold on to. Instead, he made himself nothing. He took on the very nature of a servant. He was made in human form. He appeared as a man. He came down to the lowest level. He obeyed God completely, even though it led to his death. In fact, he died on a cross. So God lifted him up to the highest place. He gave him the name that is above every name. When the name of Jesus is spoken, everyone's knee will bow to worship him. Every knee in heaven and on earth and under the earth will bow to worship him. Everyone's mouth will say that Jesus Christ is Lord. And God the Father will receive the glory." Philippians 2:3-11
Humility is thinking toward others in the same way Jesus does.
He thinks about their needs and how He can meet them. Do you?
He counts others as more important than Himself and considers what is in their best interest.
He gave up His position and privilege to serve others.
He sacrificed His very life to save the eternal life of others.
Who can match the example of humility modeled by our Savior? Who has stooped lower than He did? Who suffered more that Him for the sake of others? Who has sacrificed more than Jesus?
He humbled Himself to restore harmony in the universe. He died and rose again so that it would be possible for harmony to be preserved among His people.
In short, to have humility you must have the mind of Christ. How does that happen?
"Therefore, I urge you, brothers and sisters, in view of God’s mercy, to offer your bodies as a living sacrifice, holy and pleasing to God—this is true worship. Do not conform to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God’s will is—his good, pleasing and perfect will." Romans 12:1-2
Humility comes as a result of humbling yourself to God and allowing Him to purge your pride and self-centered mind and your self-seeking heart. In other words, harmony begins by getting yourself in tune with God - heart and mind.
Have you done that?