I feel like most of my problems with this book are due to it being published in 1955.
Customs and Folkways of Jewish Life is, well, just like it says. It starts with conception, with rituals to ensure fertility, then through birth, infancy and circumcision, childhood, becoming a bar mitzvah, getting married, dying and being buried, and then ending with a chapter on dietary laws. A lot of it is about things that I already know, like sitting shivah or that pigs are unclean, but I guess they're in here for completeness.
There were some neat customs scattered throughout I hadn't heard of, like planting a tree when a child is born and then chopping down the couple's trees to make a chuppah, which probably fell out of favor in America due to there being no guarantee of living in the same place for 20-30 years. Hanging amulets up to keep Lilith away from a child isn't common either, and while I knew about that I did not know that one version of repelling her involving having a get drawn up! That's fantastic! Similarly, there's mention of following a funeral procession for a few steps as a way of symbolically joining it, which I really like.
Most of the book, though, suffers due to its time period. This is partially due to the way that Gaster writes constantly about “primitive cultures,” which made me cringe a bit when I read it. But the greater sin is that at least half the book isn't dedicated to Jewish customs at all, it's an enumeration of all the various other cultures in the world that have practices similar to whatever the subject of discussion is. This is valuable when it's pointing out that certain practices are borrowings from neighboring cultures, like naming a baby at the brit milah instead of at birth--birth is the ancient practice and is repeatedly attested to in Tanakh--but it's much less valuable when it's just a listing of other cultures that happen to get married under some sort of canopy or that also have dietary laws.
That last one is especially egregious, because there's a discussion of several cultures that don't eat particular animals due to a belief that doing so will take on the negative qualities of that animal, and then a endnote that there's no evidence the Jews ever believed in anything similar. Great use of space in Customs and Folkways of Jewish Life, isn't it?
I get it. Back in the 1950s, we were much more of a marginalized minority than we are now. In that context, it's valuable to take practices that seems strange and Other to protestant Americans and explain that they actually have similarities to cultures all over the world. In addition, that kind of search for universality was a greater feature of anthropology 70 years ago than it is today. But it makes the book much less interesting than I was hoping.
And none of that is even touching that the book is mostly focused on the Ashkenazim, with some mention of the Sephardim and almost no mention of anyone else. I'm sure Romaniotes and Italkim have their own practices I'd like to know, and while there some mentions of Mizrahim ("Oriental," as the book states) practices, there aren't enough.