A reader recently mentioned that she had attended a shiva house and been told rather forcefully that her choice to sit down next to one of the mourners was (1) inappropriate and (2) bad luck.
I have to admit that this particular custom was new to me, but that it didn’t surprise me. Communities and families have very particular customs around death because it is a frightening time: we seek predictability and tradition in an effort to make the world seem a little less terrifying. Also, the house of mourning is sometimes a place where tact is in short supply, since people are already upset. All we can do, when we stumble into a mourning custom that is old for someone else but new for us is to apologize and be kind.
Minhag Hamakom, “the custom of the place,” is a powerful force in both Jewish law and Jewish good manners. The simplest way to explain it is the maxim, “My house, my rules.” If I am visiting the home of someone who has the custom of cutting challah with a knife, I don’t complain, even though our custom at my home is to tear the challah. It is their house, so we follow their rules.
In the synagogue, this applies too. It is bad manners to visit a synagogue and then complain to the regulars that they are doing things improperly. A visiting rabbi has to tread very carefully in this respect, as does any other visitor. I can say my prayers the way I like quietly, but I don’t make a production of it.
Judaism is full of regional customs as well. The first time I visited a Reform synagogue in the Southeastern US, I was completely shocked, because the service seemed so different from the custom in my Oakland, CA home congregation. As I became better educated, I learned that there were reasons for the differences, and I grew to appreciate them. Fortunately, my mentors had taught me not to make a fuss, so at least I didn’t leave the good people of Louisville, KY, with the impression that Californian Jews are rude!
When we find a surprising Jewish custom in a new place, be it someone’s home, or a synagogue, it is traditional to conform as best we can to the local custom. I find it is helpful to cultivate a curious mind about these things: “Oh! That is interesting! What is the reasoning behind it?” Just be aware that the answer may be “we have always done it this way” or “all PROPER Jews do it this way.” If you get those answers, you can always find an “Ask the Rabbi” online and leave the question there!