Filipenses 1:5

The reason Paul was always joyful as he prayed for the Philippians was their participation (NASB) or partnership (NIV, lit. fellowship, Gr. koinonia) in the gospel.

"It does not take much reading of Paul’s letters to recognize that the gospel is the singular passion of his life; that passion is the glue that in particular holds this letter together. By ’the gospel,’ especially in Philippians, Paul refers primarily neither to a body of teaching nor to proclamation. Above all, the gospel has to do with Christ, both his person and his work." [Note: Fee, p. 82.]

The fellowship in view, as the use of this word in the New Testament indicates, means sharing together with mutual activity and mutual benefit in a close bond. [Note: Theological Dictionary of the New Testament, s.v. "koinonos," et al., by Friedrich Hauck, 3 (1965):798.] Partnership in the gospel includes partnership with God and with other believers that the gospel makes possible. It also involves participation in the work of getting the gospel to people. The Philippians had recently sent Paul a gift (Philippians 4:10-14) and had done so more than once before (Philippians 4:16; 2 Corinthians 11:9). Even in Philippi he had received hospitality from Lydia (Acts 16:15) and the Philippian jailer (Acts 16:33-34). However, Paul’s use of koinonia here implies a broader meaning than just physical assistance. It probably includes all that Paul and his readers shared as committed Christians who sought to disseminate the gospel.

"Paul’s letter to the Philippians can be ranked as the second most important source for study of the biblical principles of financial stewardship. Only 2 Corinthians 8, 9 provide a more extensive discussion of the topic." [Note: John F. Brug, "The Principles of Financial Stewardship in Paul’s Letter to the Philippians," Wisconsin Lutheran Quarterly 86:3 (Summer 1989):215.]

"We today might take the lesson to heart that the sign of our professed love for the gospel is the measure of sacrifice we are prepared to make in order to help in its progress. We rejoice that we have come to know the Saviour. What are we doing to make Him known to others?" [Note: Martin, p. 61.]