Q. What is the optimum size for a synagogue?
A. The Talmud (Sukkah 51b) describes a grand synagogue in Alexandria, comparing its glory to the Holy Temple. But it was so big that the officiant could not be heard, and by a system of signals people were notified when to say Amen.
These days people in such large synagogues clamour for microphones on Shabbat and festivals and express their hearty disapproval when the request is denied.
The fact is that a shule that is so big that worshippers are an audience with acoustic problems, has passed the limits of what is reasonable. The service tends to become a performance and the rabbi a master of ceremonies. I cannot quantify what I mean, but instinct should tell when the shule is big enough.
A second criterion is membership. A certain Sydney rabbi used to boast that he had the largest congregation in the country. I decided to check out his claim. By adding up the list of members of his shule and mine, I proved that I had more members than he did.
I don’t know the situation today, nor does it matter. Both of these congregations are too big.
Over 500 members is too large to have a feeling of involvement with each other.