Therefore, my beloved, as you have always obeyed, so now, not only as in my presence but much more in my absence, work out your own salvation with fear and trembling,  for it is God who works in you, both to will and to work for his good pleasure. (Philippians 2:12-13 ESV)
One of the reasons this is an often misunderstood passage is because usually when I hear it quoted or referenced, only half of it is quoted. And honestly there is a bit of mystery to it, at least to me anyway, because we see the intersection of God’s sovereignty and man’s responsibility. That topic is way too large for me to even begin to tackle here, but I did have a few thoughts I’d like to share that may help us think rightly about this passage, where we are both encouraged and exhorted.
We have to avoid the two ditches. The two ditches I see being antinomianism (no law) or works-based righteousness. Misunderstood, this passage could serve as a springboard for someone to twist Scripture and lead others astray, possibly missing the gospel all together.
The antinomian’s cry would be “I’m not under the law, I’m under grace!” And right they are, if “the law” is understood as the Mosaic covenant by which God’s acceptance comes through obedience. He or she might also say “I’m a child of the King!” Again, absolutely correct, as we rightly understand the beauty of the doctrine of adoption. Yet what they tend to either not see or forget is that the New Testament is chock full of commands and rules (laws) that are given to born again, Spirit-filled believers, saved by grace through faith. And the God they call Abba, Father is still the same holy, just, Almighty, Creator of the universe that He was before they were adopted, and is still infinitely worthy of respect and obedience! He is our Father… and He is still God.
At the same time, it is equally destructive to take this passage and beat people over the head with it; making genuine believers doubt their salvation because they aren’t working hard enough. This passage does not teach works-based righteousness or salvation. To teach that you would have to divorce this verse from the grace-filled teachings seen throughout the entire Bible. Real Christians still sin. Thankfully the gospel is exactly that… Good News! The good news that we are saved by God’s grace alone through faith alone in the finished work of Christ alone saturates the New Testament (Eph. 2:8-9).
Along the same lines, neither does this passage teach that you can lose your salvation, if indeed you have been converted to Christ by the power of the Holy Spirit. I don’t have space here, again, to get into the AMAZING doctrine of eternal security, but suffice it to say that once you have been born again by grace alone you can’t be unborn. You did nothing to earn it to begin with and nothing you can do will make the Father unadopt you!
Gospel Empowered Obedience
So, what then does it mean? Why IS it here? I think the Holy Spirit tells us this for a couple of reasons (there certainly may be more!). Reminder and exhortation. I think He is reminding us of the salvation we already have in Christ, and the fact that we have been made alive so that we can obey God and grow in holiness. We are to work out what has been done on the inside of us. We are to live like the new creation we actually are. It is an exhortation to live in a dark world as lights pointing people to the One, True, and living God.
I love Paul’s writing style. He follows up a heavy command like this with the beautiful promise and reminder of God’s grace. “for it is God who works in you both to will and to work for His good pleasure.”
Christ gives us the command to humble ourselves, serve, love. Christ provides us with the ultimate example of humble sacrificial service. Christ saves us and places His Spirit in us so that we both desire to obey and have the power to obey. And Christ mercifully forgives us when we selfishly disobey, leading us to repentance.
ALL of the Christian life is grace! Why would we not work out our own salvation…?