12 Therefore, my beloved, as you have always obeyed, not as in my presence only, but now much more in my absence, work out your own salvation with fear and trembling;
13 for it is God who works in you both to will and to do for His good pleasure.
therefore (v.12) — looking back on the example of Christ in verses five through eleven
always obeyed (v.12) — beginning with the obedience of faith (Romans 1:5)
in my presence (v.12) — when Paul was in Philippi
much more in my absence (v.12) — when Paul wasn’t there to lead them and they had to depend on Christ
work out (v.12) — bring about a result by diligent effort. It says “work out,” not “work for” your salvation.
salvation (v.12) — the present experience of deliverance from evil — the realization of the power of God to do His will, commune with Him and be victorious over sin (as Paul did in 2 Timothy 4:7).
There are three aspects of salvation: past (justification); present (sanctification); and future (glorification). Sanctification is “worked out” in us by God with our free will. God works in us to want to, but wanting to doesn’t accomplish the desired objective. We have to actually do what God worked in us to want to do or we will never reach the goal of letting “this mind be in you … ”
Even in sanctification, our standing before God is perfect in Christ. But our state is the practical outworking of our standing. This is what Paul has in view here. They were to carry their salvation to its ultimate conclusion — Christlikeness
fear and trembling (v.12) not dread but watchfulness to avoid displeasing God — a reverent and constant consciousness — a fear of spiritual failure. These two words are always (in Scripture) used together to in relation to obedience. The fear here is self-distrust, taking heed lest we fall.
God who works in you (v.13) — emphasis is on “God” — the working isn’t ours but is God’s in-working
to will (v.13) = to desire. God gives us the desire and the power to do His will.
good pleasure (v.13) — with a good object in view. God acts in us to bring about good for us.
These verses highlight the believer’s responsibility and free will.
Paul was encouraging the Philippians not to miss an opportunity to give God their very best.
In verse 12, we have human responsibility, in verse thirteen, divine enablement, a perfect balance which must be kept if the Christian life is to be lived at its best. It is not a “let go and let God” affair. It is a “take hold with God” business. It is a mutual co-operation with the Holy Spirit in an interest and an activity in the things of God. The saint must not merely rest in the Holy Spirit for victory over sin and the production of a holy life. He must in addition to this dependence upon the Spirit, say a positive NO to sin and exert himself to the doing of the right. Here we have that incomprehensible and mysterious interaction between the free will of man and the sovereign grace of God. — Philippians in the Greek New Testament, by Kenneth S. Wuest, pages 74-75.