Hands down, my favorite quote about books or reading is this one from Steven Wright: "I'm writing a book. I've got the page numbers done." My second favorite is a quote from Doctor Who: "We're all stories in the end. Just make it a good one." (I have one of those inspirational cuff bracelets with this quote on it, cuz I am a hardcore fangirl like that.)
I bet you were hoping for something more profound, hmm?
Truth is, my lived experience is not all that profound. Books were sanctuary for me when I was growing up. I spent a lot of time in the public library, and then I went home and read some more. Books were instructional and safe and dependable. I guess you could say books raised me, so I think of them as a beloved granny maybe, not a magical portal or secret religion. Or, as Oprah Winfrey put it, "Books were my pass to personal freedom."
So in a sense, the truest truth would be to say that books are practical magic.