ISB ~ Philippians 2 v12

work out your own salvation:i.e., make continued efforts at living the gospel and pursuing your heavenly reward. The statement assumes that while our initial salvation had nothing to do with our works (Eph 2:8-9), our final salvation depends on a lifetime of keeping the faith (2 Tim 4:7-8), following the commandments (Mt 19:17), persevering in good works (Rom 2:7), striving for holiness (Heb 12:14), praying in earnest (1 Thess 5:17), and fighting against the forces of evil (Eph 6:11) and the selfish demands of the flesh, which drag us down (Rom 8:13; 1 Cor 9:24-27). This obligation is so serious that we pursue it with fear and trembling, i.e., with a sense of awe at serving the living God and a sense of dread at the prospect of sinning against him (Ex 20:18-20; Ps 2:11-12). Encouragement comes in the next verse, where Paul reminds readers that God’s grace is working actively within them both to desire (intention) and do (act) what pleases him (Heb 13:20-21; CCC 308) (CCC 1949).

• When Paul commands them to “work”, he addresses their free will. When he adds “with fear and trembling”, he cautions them against boasting as if their good deeds were their own. If you fear and tremble, you will not boast of your good works, since it is God who works them within you (St. Augustine, On Grace and Free Will 21).