The pattern running through West Germanic religious history is translation. Gothic, which belongs to the East Germanic branch rather than to this one, set the precedent: Ulfilas devised an alphabet in the fourth century in order to translate the Bible, and Gothic survives almost entirely as that translation. Nearly every Germanic language afterwards received scripture the same way, through a deliberate act of rendering rather than through gradual absorption.
Aelfric in Old English, the Otfrid gospel book in Old High German, the Dutch and Low German bibles of the fifteenth century, and then Luther's German New Testament of 1522 and complete Bible of 1534, are stages of one process. Luther's translation is the case with the largest consequences, because it fixed a written standard for German while making an argument that scripture belonged in the hands of people who could read only their own tongue, and the printing press carried both effects together.
William Tyndale did the same for English and was executed for it in 1536, and much of his wording passed into the King James Version. Yiddish, a West Germanic language written in Hebrew script, developed its own religious literature, including a Yiddish retelling of the Torah made for women and read in households for four centuries.