Whilst laying low at Wartburg Castle, Luther turned his attention to translating the bible from Greek to German. In doing so, he produced a seminal literary work which played a significant role in creating a modern German language.
Prior to Luther's translation, the bible was a text that most laypeople had never read themselves: Churches had latin bibles and the handful of German translations in circulation were written in such a stilted manner that they were mainly used for academic purposes.
For his translation, Luther used an ancient Greek bible upon which subsequent, and often inaccurate latin versions were based. In doing so, he was able to convey the original messages of the scripture whilst utilising a form of German that was close to that spoken by "mothers at home, and the average man at the market", as Luther said when describing his approach to the translation.
In doing so, Luther would have an enormous impact on the German language, coining a vast number of expressions and turns of phrase that are still used to this day including Lästermaul, Machtwort, Schandfleck as well "Wolf im Schafspelz" (lit. 'wolf in sheep's fur', wolf in sheep's clothing) and "Zähne zusammenbeißen" (lit. 'biting one's teeth', to knuckle down)
Luther completed his 220-page translation within an astonishing eleven weeks. After leaving the 'Wartburg' in March 1522 after ten months in hiding, Luther added the finishing touches to his bible before publishing it in September later that year.
Three thousand copies were printed, a vast amount for the time, which quickly sold out, with a second edition following three months later. As Luther's translation spread throughout the nation, so did his unique yet familiar take on the German language. Within a short amount of time, Luther's bible had spread to all parts of life withing the German-speaking world, making Luther a highly influential figure.