Faith magic effective against spirits

I shuddered and secured the little braid of musty cloth and silver chain about her wrist, willing enough energy into it to close the circle once the knot was tied. When I finished, I touched her forearm lightly. I could just feel the talisman's power, a tingling sensation that hovered a half-inch off of her skin.
"Faith magic works best against spirits," I said quietly. "If you're worried, get to a church. Spirits are strongest just after the sun goes down, around the witching hour, and again just before the sun comes up. Go to Saint Mary of the Angels. It's a church at the corner of Bloomingdale and Wood, down by Wicker Park. It's huge, you can't miss it. Go around to the delivery door and ring the bell. Talk to Father Forthill. Tell him that Michael's friend said that you need a safe place to stay for a while."
She only stared at me, her mouth open. Tears formed in her eyes. "You believe me," she said. "You believe me."
I shrugged, uncomfortable. "Maybe. Maybe not. But things have been bad, the past few weeks, and I would rather not have you on my conscience. You'd better hurry. It's going to be sundown soon." I pressed some bills into her hand and said, "Take a cab. Saint Mary of the Angels. Father Forthill. Michael's friend sent you."

Grave Peril Chapter 4, Page 34