Let's see..

Given that I think he would call his friend Father Calbor, the priest with a small church near Thaum's home. Calbor owes him a great debt after saving Calbor's daughter from demonic possession. He tried to give Thaum gifts and offers of help with the spiritual. Thaum however only rarely asked for old books or for a safe place to sleep on hallowed ground after a demon or undead creature had decided to claim his life. The priest is always happy to help even at strange hours because of the debt Calbor is trying to repay.

How's that?