Much of what occurs at church (in a Mass, say) is symbolic. (It can also be sacramental, which is at least symbolic.) Therefore, to understand what is going on in a Mass, it helps to understand the symbols.
Symbols point. So, much of church architecture or of, say, a Mass, is referring to things beyond itself. It is like a book, that can be read (and read with different interpretations).
So, in a church a candle is not simply to generate light – it usually symbolizes something else, such as the light of God that dwells in a human. And so on. Often, the symbols are compounded – that is, one symbol takes on meaning in reference to another symbol (for example, incense gains some symbolism because it rises upwards – but that refers to another symbol, that of upwards as where divine reality is, and so on).
If one does not know that much of what is occurring is symbolic, and then have some understanding of the symbolic language, churches or Masses, say, lose much of their meaning. It is like reading a book where one does not understand the alphabet or language in which it is written – or where one doesn’t even realize that the ink splotches on the pages refer to anything.
It is not only like reading a language, it is also like learning a language – building up a conceptual repertoire and connecting those to symbolic references to the things those concepts are about.