Question:
Whats the orgins/source of those listening to havdolah to first say the phrase layehudim etc?
Answer:
I don’t have a good source for this minhag, however as with other minhagim, although we don’t know the reason, we still continue to do them. As the Rashba wrote, that we shouldn’t be lax regarding the minhagim that Klal Yisroel does, that we don’t know the reason, because if it has been done this way for generations, there surely was a good reason for it. See Be’er Moshe 8-36(3).
Best wishes
