Therefore, if there is any encouragement in Christ, any comfort provided by love, any fellowship in the Spirit, any affection or mercy, complete my joy and be of the same mind, by having the same love, being united in spirit, and having one purpose. Instead of being motivated by selfish ambition or vanity, each of you should, in humility, be moved to treat one another as more important than yourself. Each of you should be concerned not only about your own interests, but about the interests of others as well. You should have the same attitude toward one another that Christ Jesus had – Philippians 2:1-5
In 1:12-18 Paul showed us that he rejoices that the gospel is being preached whether in rivalry or goodwill.
In 1:19-26 he stated that to die and be with Christ is far better on his account, but he would rather stay for the progress of their joy because it is a fruitful labor for him.
And in Philippians 1:27-30 he told us what this progress of joy is, namely to live a manner of life that shows the worth of the gospel by being united and with fearlessness in standing firm, contending for the faith of the gospel.
So in staying, Paul’s joy is somewhat incomplete since there is rivalry instead of unity. Therefore to see God working in the lives of the Philippian believers and see them being united will complete his joy.
If (ei). Paul uses four conditions in this verse, all of the first class, assuming the condition to be true.
Paul is not doubting that encouragement, participation in the Spirit, affection, and sympathy are realities in Christ and are present in the congregation at Philippi. He uses a conditional sentence (if) to provoke the Philippians so that they will reflect on whether these qualities are evident in their lives. This is to give basis or grounds for the commands.
This shows that not just what we know about the truth that gives reason for the imperatives in Scripture but what we also feel about them. Encouragement in Christ, Comfort from love, Fellowship in the Spirit, Affection and sympathy, all of these has to do more with our hearts than with our minds. Christian unity must flow from compassion.
The joy that Paul aims to be completed by them is their unity and this unity is done by:
not even from pride or vain glory
Be concerned not (only) about your own interests but and(also) of the interests of others.
“The word interests is a filler. In the original, it’s open-ended. All that is specified is “your own (something)” or “the other’s (something).” So it could be, “Let each of you look not only to your own financial affairs, or your own property, or your own family, or your own health, or your own reputation, or your own education, or your own success, or your own happiness―don’t just think about that, don’t just have desires about that, don’t just strategize about that, don’t just work toward that; but look to the financial affairs and property and family and health, and reputation, and education, and success, and happiness of others.”-John Piper
No, because as we saw from Paul’s example, he was convinced to stay because it is necessary for their account. By denying himself of private pleasures or self interest, he gain more joy in the joy of others.
No, because this mindset, namely a kind of unity that demonstrates itself in humilty and love is in Christ (verse 5)
Therefore to attain true humilty, love and unity our joy must be the interest of others, and we can do this because we have this mind in Christ.