What does 1 Thessalonians 3:8 mean?

Seeing the Thessalonian believers standing firm in the Lord filled Paul's life with joy and a sense of fulfillment. The word for "standing" derives from the Greek word, stekete, a military term that describes soldiers firmly holding their ground against an enemy. The believers at Thessalonica were holding their ground against attacks from the Devil and his forces. False teachers were trying to detour them from the truth, and persecution was fierce. Nevertheless, they stood firm. They grasped the anchor of hope firmly so they would not drift away from the faith (see Hebrews 6:19).

Firmly planted in the faith and holding onto the anchor of hope, they were doing what Paul exhorted the Corinthian Christians to do. They were "steadfast, immovable" and "always abounding in the work of the Lord" (1 Corinthians 15:58). In a similar exhortation, Paul wanted the Philippian believers to stand firm "in one spirit, with one mind striving side by side for the faith of the gospel" (Philippians 1:27). Collectively, Christians can be stronger than an individual believer in standing against the Devil and his forces.