Ah, your extraordinarily beautiful bookshelves, dense with interesting carvings and books bound in beautiful colors and patterns. You inherited these from your creator, along with the portion of their library that survived the intervening centuries. Only the mystical literature is really still relevant, since back then nobody knew anything useful about angelic alchemy or astrology. Source interpreters hadn't even been invented yet! Sometimes you look at the diagrams of how your creator had to go about contacting angels when you need a laugh.
Mostly you keep the library because if you only had the books you've bought yourself, the shelves would look pitifully empty for the study of such a powerful sourceror. Basically you love to look at your bookshelves and you pity the vast majority of sentient beings who don't get to see their magnificence.