Quest for the grimoire

Following advice from my post on the subreddit, I prepared myself.
- Spellbook? Check
- Icebolt? Check
- Unlocking spell? Check
- Lockpicking kit? Check
- Defensive spells? Check
- Rune dictionary? Check
- Curse-proof charms? Check
- Scrying-safe room? Nearly done with a temporary one, and a bigger one has been ordered and should arrive soon.
- Glock-17 Wand? Check, loaded and illusioned as a torch. (I’m doing with what I’ve got, okay?)
I arrived on site at about 10 in the morning. Five minutes later, a resident let me in. After going to the door they showed me yesterday and making sure no one was around, I opened my spellbook and cast the unlocking spell. I felt something break, but the door didn’t open, so I got my lockpicking set. Fifteen minutes later, I had cracked it.
A loud creak echoed through the hall as light was shed on a 200-year-old room. Not a speck of dust passed through the magic lock, but the smell of the plants and ingredients in the room concentrated over the years and nearly made me choke.
In it, racks upon racks of herbs, plants and roots. Wooden shelves lined the walls, filled with minerals, jars and contraptions of unknown origins. In the middle, a long table with a ritual circle inscribed in the wood. On it, a book open. Next to it, the mummified corpse of the wizard.
One of the charms burst into flames as soon as I entered the room, signalling that a curse was blocked, at least temporarily.
One down, two left.
A voice boomed in the room:
“Wizard of new who entered my room, take care. A disease wiped us out, and it will end you too should you not. Anything with our magic spreads it. Anything with our flesh carries it. Anything with our memory embodies it.”
As soon as I heard the voice, a warmth became felt through my shirt. In addition to the two normal curse protection charms, I had gotten a “block any and all magical effect from affecting me, once” pendant from someone trustworthy on the forum. Looking down, I saw that it had started to shine brightly.
Then, my eyes landed on the book and I knew that I found the grimoire, but the heat on my chest intensified.
“Stay away from our tombs, for we chose to seal it with us. To sacrifice our knowledge so that life may persist and magic may one day be reborn.”
I closed my eyes in the hopes that it would reduce the heat, to no avail.
“We have only one advice for your new civilisation of magic. One chance for you to find a cure: the mobile library will need a firm foundation if it wants to eradicate the silverfish.”
With the message spell finished, I immediately headed out of the room and closed the door. With the locking spell reengaged behind me, the protection charm finally broke.
Now that I’ve returned to my abode, can someone PLEASE help me figure out what this means? I don’t think I can deal with this alone… I think the pendant counted the spell and its infection as a single “attack”.