Philippians 1:6
Philippians 1:66being confident of this, that He who began a good work in you will carry it on to completion until the day of Christ Jesus.
The Watchtower does not prominently feature this verse, as its message — that God himself will complete the work he began in the believer — undermines the organisation's emphasis on personal performance and endurance as conditions for salvation. When referenced, the "good work" is reframed as the preaching activity of the organisation rather than God's transformative work in the individual believer.
Paul expresses confidence that "the one who started a good work in you will bring it to completion by the day of Christ Jesus." The subject is God, not the believer — God initiates, God sustains, God completes. This is a promise of divine preservation, not a command to try harder. Combined with ("no one will snatch them out of my hand"), (nothing can separate us from God's love), and ("so that you may know"), the verse grounds assurance of salvation in God's faithfulness rather than human performance. The Watchtower's system — where no one can be certain of salvation until Armageddon — directly contradicts Paul's expressed confidence here.