A portion of Phi 2 forms a chiastic structure:
1a) Phi 2:1-4, Be like minded, without conceit or selfish ambition, looking out for the interests of others;
1b) Phi 2:5-11, Christ Jesus became as a bondservant, to serve as the sacrifice of God on the cross;
1c) Phi 2:12-13, Work out your own salvation with fear and trembling, God working in you;
1d) Phi 2:14, Do all things without complaining or disputing;
1e) Phi 2:15a, That you may become blameless and harmless;
central axis) Phi 2:15b, Children of God;
2e) Phi 2:15c, Without fault;
2d) Phi 2:15d, In the midst of a crooked and perverse generation, among whom you shine;
2c) Phi 2:16, Hold fast to the word of life, so that in that Day I will not have labored in vain;
2b) Phi 2:17-18, Paul poured out as a drink offering on the sacrifice of the church’s faith;
2a) Phi 2:19-24, Timothy: like minded, caring with sincerity, not seeking his own but the things of Christ.
Paul does not mean, I believe, that it is when we have attained to faultlessness, that we become children of God. But a child, when he is born into a family, is brought up in nurture and discipline to become conformed to that family. Thus when the child is grown, his conduct and actions declare for him to which family he belongs.
Likewise God’s children also have distinguishing characteristics, when God brings them up through His nurture and discipline (God working in them as they hold fast to the instruction in the word of life). We will stand out from the crooked and perverse generation which is around us.
How? The crooked and perverse generation seeks its own interests. The children of God seek to serve the interests of others. The crooked and perverse generation is ruled by selfish ambition and conceit, whose aim is self gratification. The children of God are ruled by humility, whose aim is self sacrifice. The crooked and perverse generation complain and start disputes. The children of God do not cause harm in their course of life.
This is why Paul says, work out your own salvation with fear and trembling. We enter the kingdom by faith, but faith always produces fruit as evidence of its existence. Paul does not want the church to be deceived — since there were some in the church, whom Paul warned the Philippians about, who were evil workers — into thinking that mental assent to the things of God equaled saving faith with the evidence of fruit which shone like light in the world.