Do nothing from selfish ambition or conceit, but in humility count others more significant than yourselves. (ESV)
I can remember being told as a child to think before I acted. That's good advice for all of us at any age. The Apostle Paul loves the church that God has established. He wants the church to be unified and effective in proclaiming the Gospel. That's why he gives instruction on what motivates our behavior. We are not to do things from selfish ambition or conceit, but rather humility.
There are many churches that are havens for people who war with one another. Each person demands their own way. The stronger members form coalitions of people who agree with them. Perhaps, it is a group of family members who put a stranglehold on any efforts to bring any necessary change to the church for fear of them losing any of their power.
Paul is saying that if our motivation for doing anything is from selfish ambition or conceit (striving to get one's own glory) it is wrong. It is important for us to realize that this could even include things that in and of themselves are not wrong. For instance, it may not be wrong to contribute money to the church, but it is wrong to give it so that you can boast about it. It may be right to use your gifts for the Lord, but those gifts will be worthless to the Savior if your heart is not humble before him.
Being part of the church is not an easy thing. I am sure that is why many people who love the Lord drop out of regular church attendance. They are wrong for giving up on the church, but it can be understandable to be frustrated by the regular actions of Christians. We are supposed to count other more significant than ourselves. Can you imagine if the church actually heeded this instruction?
Think before you act. Even if you are planning on doing something that is a good thing. What is your motivation? Is it to glorify God or yourself?