Putting it more simply, encouragement comes from a relationship with Christ. In this relationship we know we are comforted in His love. The Spirit is in the midst of this relationship and creates a fellowship with Him and with those around us who are in Christ. If we acknowledge these things in our life then the expression of such things will show in our compassion and tenderness for one another.
In light of this Christlike attitude, we would agree with each other, we would love one another, and we would work together in harmony exhibiting like minds and like purposes. We would not be people who are selfish - we would be generous. We would not be people who make efforts to impress one another. We would be humble and not think we are better than everyone else. I believe as far as better goes, there is no one better than another and likewise, there is none worse. We are all unique and stronger at some things while being weaker in other things. If you balanced all these things out no one would stand as being better or worse, but simply different.
Paul continues also saying that we would not be people who only look out for our own best interest while ignoring the interests of others. There were apparently issues and some jealousy in the church at Philippi which Paul was addressing. While this letter addresses their issues, it is a great teaching and/or wake up call for us. Living in such a way would make them all united as fellow followers of Christ rather than the division not living this was causing.
He wraps it all together saying that if we are truly in a relationship with Christ then we must have the same attitude as Christ. He then goes on to give examples how Christ's life expressed His attitude. He did not elevate Himself to equality with God. Rather, He gave up all His divine privileges and humbled Himself to become a slave and mere human. Jesus was humble before His followers. He showed humility before those who persecuted Him. He humbled Himself taking on the false accusation of being a criminal. He humbled Himself by allowing Himself to be crucified on a cross. He humbled Himself in all these ways in obedience to God. He gave up all things of His heavenly rein in order to be part of God's own plan for the salvation of man kind. He gave it all away to play His part in obedience to God. This makes me wonder how deep my relationship with God is. It makes me wonder how far I would be willing to go in humility to play my role in His plan. It brings up good questions about the level of my devotion to Him.
In response to Christ's humbling Himself to become obedient to the Father, He was elevated by the Father to the place of highest honor. The Father made Jesus the name of honor above all names. All would realize Jesus' position and all knees would bow to Him in heaven and on earth. Every tongue would one day confess that Christ is Lord all to the glory of God the Father - even those who would mock Him and call Him a liar. Christ's life, humility and sacrifice would bring the Father glory and honor. Again, this makes me reflect and wonder how much glory does my life bring the Father. On the other hand, what areas of my life actually bring Him shame or embarrassment?
Paul points out that when he was among the church in Philippi, they always followed and practiced what he taught. Paul implies that it was easy for them while he was in their midst but that it would be harder now that he was gone. It would require them to try harder and to use more effort to live with the attitude of Christ as he had been teaching. He encourages them to live in a way that expresses their relationship with God and their faith. He reminds them they are not alone for God is in them working to give them the desire and power to do what pleases God.
Many times in Scripture we are told not to complain while we do things (being reminded of the way the Israelites complained to God during their escape from Egypt. This plea may have been given remembering how their complaining adversely impacted their relationship with God.) We are also told not to make bold public displays that draw attention to ourselves but to live the Christian life in innocence with our lives as shining light illuminating truth in a world of crooked and perverse people. This should encourage us to live in such a way for we too live in such a time.
He encourages them to hold firmly to the Word and to what they have been taught. He also promises that when Christ returns he (Paul) will be proud of what they have done and that his work mattered. Paul states that he would be proud if he poured his life out in service to God even to the point of death. He would rejoice having lived such a life and he wants the same for them. Having lived lives such as that, they would all be filled with the joy of a life well lived.
Paul mentioned that many people only care for themselves and not for the things that matter to Christ. He tells them that he hopes to send Timothy to them and that Timothy is not such a person. He promises that Timothy genuinely cares for their welfare. He doesn't just say that but expresses that Timothy has proven himself by serving him (Paul) as a son serves his father and by preaching of the Good News.
Paul not only hopes to send Timothy to them but also hopes to visit them soon.
The Philippians had sent Epaphroditus to help Paul. Paul praises him for being the kind of man he is. He had become ill, nearly to the point of death, from working too hard and Paul felt it best to return him home to Philippi. Paul praised God for His mercy in not allowing him to die. Paul wanted no one to think of this as a failure but rather to welcome Epaphroditus home with love and to honor him as such a person deserved. He was a man who risked his life, nearly giving it for the work of Christ.