Summary: Demonstrates how unity and fulfilling the purposes of the church go hand in hand. Gives practical characeristics to exhibit in order to achieve unity.
Unity in the Church
Here Paul is instructing the church how they are to act one to another. He’s leading them to unity. And it’s unity for a purpose. Vs. 2 says "working together with one heart and purpose." It’s when we follow these instructions of Paul and we, the Church, are united, that we will accomplish our purpose. There are three purposes for the church. To worship God, to build up the saints, and to spread the Good News. And unity is important for all three of these purposes. When we are united, it leads to God being glorified. vs. 11 speaks of Jesus’ exhibiting the same characteristics that Paul is admonishing us to exhibit, and he says it led to the exaltation of Jesus, "to the glory of God the Father." When we follow the command to be interested in others, that leads us to help build them up. Therefore, this unity leads to building up the body. And as Jesus said to his disciples, "Your love for one another will prove to the world that you are my disciples." (John 13:35 (quickview) ) So unity is important for accomplishing all three purposes of the Church.
In order to see what is necessary for us to achieve unity, let’s look at the four things Paul admonished the church in Philippi to do. Together with that, we see that he gives the example of how Jesus demonstrated for us each of the qualities Paul was now admonishing the people to exhibit. In fact, verse 6 to 11 are an earlier hymn of the Church, which Paul is using as an illustration. The people to whom he wrote would recognize this hymn. They would already have known these qualities of Jesus from singing about them so often. And now Paul is using this as a basis to teach them how they can live in unity. We too can glean from Christ’s example here.
I. Don’t be selfish. (vs. 3) The society in which we live is a very self oriented society. The big question we ask when we have a decision whether to do something or not is, "What’s in it for me?" or "How will I benefit from this?"
However, the Church is not selfish. For the Christian, the question should not be, "How can this benefit me?" but "How can this benefit the Kingdom of God?" President JFK once said, "Ask not what your country can do for you, but you can do for your country." And if that’s true of something like an earthly political establishment, how much more true it should be of Christians and the Kingdom of God. We need to spend less time thinking of what God and what the Church can offer us, and spend more time asking God what we can do for him and his Church.
Self is all about the individual. But the Kingdom is about the body. As Ephesians 4:4 (quickview)  says, "We are all one one body." The Church isn’t made up of a lot of disconnected people. The Church is not you over there doing your thing and me over here doing my thing. Imagine if your hand suddenly decided that it didn’t want to work with your arm. Your arm and your foot just couldn’t get along. They both wanted to help you, but they had different ideas about how to do it. So, the hand decided one day that it would just do it’s own thing completely separate from your arm, so it separated itself. It would soon find that it was pretty useless without the arm. In fact, if you had 100 hands, but none of them were connected to arms, they wouldn’t be as good as one hand connected to an arm. For your body to work, it has to work together. And the Church is exactly the same. I’m sure that we all want to fulfill God’s purposes. But if allow ourselves to become selfish, then we end up all doing our own thing. It’s not that we don’t want to do God’s work, but we just don’t want to do it with Brother so-and-so or Sister so-and-so. Well, when we do that, we’re really not accomplishing anything for the Kingdom, because we’re separated from the body. We, the Church, must be a team, working together to accomplishing God’s purposes, because that’s the only way they can be accomplished.