But since we belong to the day, let us be sober, putting on the breastplate of faith and love, and the helmet of our hope of salvation. — 1 Thessalonians 5:8
Belonging to the day means believers already share in God's certain future, so their identity rests securely on what Christ has done. This settled assurance changes how the church endures present hardship, because salvation is anchored in Christ and cannot be lost. Confident hope becomes the source of sober and faithful living.