Answer:
One factor that illustrates Luther's value of the individual faith of believers is the fact that Luther himself translated the Bible, from ecclesiastical Latin, a language that only the clergy could read, to vernacular German, the language of the common German people (even if the majority of Germans at the time were farmers who could not read nor write).
With his translation, Luther wanted to make the Bible more accessible for the German people, so that each invidivual could read it by themselves, and gain personal insight from its teachings.