The now commonly-used German idiom im Dunkeln tappen for being in the dark, missing facts about something and not being able to understand completely or at all (literally meaning to grope [and toddle] in the dark) was first coined in 1534 in the German Bible translation by Martin Luther. (Source: Günther 2017, p. 59)

For other idioms or terms in German that were coined by Bible translation, see here.

Note that the German New Testament translation by Berger / Nord (publ. 1999) uses this wording in John 12:35.