The phrase in Christ appears eight different times through the letter to the Philippians and is one of the major themes that Paul addresses. The wording is important because Paul does not use in Jesus, by Jesus or even because of Jesus. Paul makes the usage in Christ for two important reasons. The first is that he is writing to Jewish converts to the faith. Making the claim that Jesus is the Christ or messiah was vital to the message Paul preached in Philippi and this was another way of reminding them of that fact.
The second reason is a bit more subtle but it is clear. Paul seems to making a clear connection to the benefit of being part of the church or body of Christ. One issue that Paul addresses with the church is unity. Communicating the fact that the believers had a common bond in Christ would go a long way in restoring the unity of the church.
Notice all of the things that Paul writes here that we gain by a relationship with Christ.
Believers are in Christ (1:1)
The life of faith that binds Christians together flows from being united in Christ. The common bond that holds the church together is Jesus. Every Christian enjoys a relationship with one another because we are in Christ.
Our joy is in Christ (1:26)
Christians understand that the source of personal and lasting joy is not in this world. Our source of joy comes from a personal experience with Jesus. The power of His resurrection brings us joy that nothing in life can ever take away.
Our glory is in Christ (3:3)
Glory is receiving honor, respect and awe from others. The glory of Jesus will be revealed at the end of time when he returns. The Christian seeks not to bring glory for themselves, but instead to glorify Christ. When Christians live to bring glory to the name of Jesus the ned result is sharing in Christ’s final glory.
Our confidence or faith is in Christ (3:9)
Christians find the source of their confidence in life is Christ. The source of being confident in daily living comes from knowing that Jesus is walking with us through every aspect of life.
Our hope is in Christ (3:14)
The hope of the Christian lies in two fundamental truths. The first is that Christians have the promise of heaven and that when we die we will have a place in heaven with Christ. The second source of hope is found at the end of time and the promised resurrection of the dead. Jesus promises to give us a new body and new life through His resurrection.
Our peace is in Christ (4:7)
The experience of peace is the weaving of divine power with our human weakness. Peace gives us stability in the midst of an insecure world. We can have rest in the midst of the turmoil of life.
Our reward or blessings are in Christ (4:19)
The reward of the Christian life is to experience eternity with Christ. The blessing of knowing Christ is the experience of His strength in daily living. The blessing of Christ is the ability to get through the difficulties of life and surviving its hardships.
Our citizenship is in Christ (4:21)
Christians have a dual citizenship. Christians have life here on earth and our future place in heaven. Christians are members of the Kingdom of Christ and have a place prepared for them in heaven.