I'm wondering if anyone has ever put together a book that lists all the different elements that can come up in the realms of Kodshim and Taharot (e.g. bulls, the number seven, water, slaughtering, etc.) along with traditional explanations for what they each may symbolize.
I realize that the idea that these elements are meant to symbolize anything, as opposed to simply being elements of God's Commandments, which we obey without worrying about their meanings, is not a universally-held opinion. However, there are those who do discuss symbolic meanings in these practices, so the book I'm wondering about would be based on their teachings. For example, R' Hirsch's commentary on the Torah makes repeated and consistent reference to many such symbolic elements.
It seems to me that such a book could be very useful when studying these areas in particular. People tend to treat them as rather esoteric, partly because they're mostly not in practice currently, and partly because they deal with essentially spiritual causes and effects that aren't obviously connected to natural phenomena that we're familiar with. With the sort of dictionary that I describe at one's side, one could analyze a complicated procedure, or even a hypothetical complicated procedure in the Talmudic debates, in part by breaking it down into its constituent elements and analyzing what each one is taken to symbolize.