Stand therefore, having the belt of truth buckled around your waist, and having put on the breastplate of righteousness
- Ephesians 6:14
Paul is countering the false teaching in Ephesus that when God would come in His armor (mentioned in Isaiah) on the Day of Vengeance, He would destroy all Gentiles on earth. Instead of being struck down, believers in Christ will stand, and Paul encourages the Ephesians to put on the very armor they were taught to fear. Also, notice what Paul doesn't mention from Isaiah: the garments of vengeance and the mantle of zeal.