The Thirteenth Tale

I'm kind of obsessed with Diane Setterfield's The Thirteenth Tale lately and keep rereading one particular passage over and over:

"How long did I sit on the stairs after reading the letter? I don't know. For I was spellbound. There is something about words. In expert hands, manipulated deftly, they take you prisoner. Wind themselves around your limbs like spider silk, and when you are so enthralled you cannot move, they pierce your skin, enter your blood, numb your thoughts. Inside you they work their magic. When I at last work up to myself, I could only guess what had been going on in the darkness of my unconscious. What had the letter done to me?"