The Book - The Man Who Loved The Truth.
A reminder! The full armour of God. The belt of truth. The breastplate of righteousness. Ready and eager with gospel message. The shield of faith. The helmet of salvation. The sword of the spirit
Another excellent text on the subject is Paul's letter to the Philippians: "Therefore my dear friends, as you have always obeyed — not only in my presence, but now much more in my absence - continue to work out your salvation with fear and trembling." ( Phil 2:12 )