This book, by Simeon (1759-1836) is a short exposition on Ephesians 6:10. Simeon provides a warning and a promise to every believer. The promise is that if we wear all the armour then we win battles, not just war. The warning is if we don’t wear all the armour we will be defeated. It’s a short read, about 160 pages, but worth reading and would bless the prayerful reading of it.