Here Paul continues to express his gratitude to the Philippians for their financial gift, careful to express that, though he is grateful for their gift, their generous and sacrificial giving are evidence of their spiritual progress and health. In fact, using language from the Old Testament sacrificial system, Paul affirms that their generous and sacrificial giving are at act of worship, an aroma pleasing to God. Such is try for our lives too when we pour ourselves out for the sake of Christ and his gospel ministry. We are living lives of worship, pleasing to God.