For the translation of this verse into Maasina Fulfulde Doug Higby tells this story:
“[We] had the word for ‘door’ and also a word for knocking or ‘hitting’ a door. But as I thought about it, Jesus was coming to visit! The Fulani don’t even have doors on their traditional huts, and they certainly don’t bang on the reed coverings used to keep the dust out of the doorway. If Jesus came, he would go to the entrance of the courtyard and say, ‘Salaam Alaikum.’ This would announce his presence in the same way that knocking on a door would in Western contexts. But I was concerned… the Greek text says ‘door’ and I wanted to be faithful to the original. Yet, I felt the Fulani customary greeting was exactly what Jesus would do in this context, so I continued. To my great surprise, the next part of the verse went: ‘Anyone who hears my voice and opens the door…’ Voice?! Who said anything about Jesus speaking, I thought he was knocking… So now the Fulani greeting makes even more sense with the cultural version which goes like this: ‘I stand at the entrance (to your courtyard) and greet (in peace). Whoever hears my voice and lets me in, I will enter and eat together with him.’ (Hettina, miɗo nii darii e damal miɗo salmina. Neɗɗo fuu nanɗo daande am so udditi, mi naatan galle mum, mi ɲaamda e mum.).”
See also knock (on door).
The Greek that is translated as “knock (on a door)” in English is translated as “call” (Zanaki, Yanesha’) “speak” (Tzeltal), or “clap” (Zarma).
This is sometimes due to the fact that doors are not being used in the respective cultures (as, for instance, in Yanesha’) or, as Nida (p. 45f.) explains, other cultural differences:
“One cannot say to the Zanaki people along the winding shores of sprawling Lake Victoria, ‘Behold I stand at the door and knock’ (Revelation 3:20). This would mean that Christ was declaring Himself to be a thief, for in Zanaki land thieves generally make it a practice to knock on the door of a hut which they hope to burglarize; and if they hear any movement or noise inside, they dash off into the dark. An honest man will come to a house and call the name of the person inside, and in this way identify himself by his voice. Accordingly, in the Zanaki translation it is necessary to say, ‘Behold I stand at the door and call.’ This wording might be slightly strange to us, but the meaning is the same. In each case Christ is asking people to open the door. He is no thief and He will not force an entrance; He knocks — and in Zanaki “He calls.” If anything the Zanaki expression is a little more personal than our own.”
Sources: Nida 1952 (Zanaki); Duff Tripp, p. 310 (Yanesha’); Reiling / Swellengrebel (Tzeltal, Zarma).
See also complete verse (Rev. 3:20) and knock (Rev. 3:20).