What language did they speak? – Vayyiggash
Joseph & his brothers, by Gustave Dore
In what language was the conversation? It could not be in Hebrew since Joseph did not reveal his real identity, and it was not politically correct to conduct a conversation in the language of visitors from elsewhere.
The conversation was probably in Egyptian and conducted with the aid of an interpreter (Gen. 42:23), even though the brothers had a knowledge of the language of Egypt – Egypt and Canaan abutted on each other – though their Egyptian was not as fluent as their Hebrew.
At a particular point Joseph told the interpreter to leave the room. Was it because he could see that the brothers knew enough Egyptian to make an interpreter unnecessary?
Probably not; he didn’t want anyone, interpreter or otherwise, to witness the family revelation that was to follow.
Rashi thinks that the brothers would be embarrassed if an outsider saw how shocked and repentant they were when they found that the Egyptian minister was the brother they had treated so badly.
Ramban adds that if the Egyptians found out that Joseph was their brother, Joseph would lose face and the brothers themselves might be denied permission to stay because if they could treat their own brother so badly they might not behave properly as Egyptians.
