How does Ned Flanders know to take the boys down to the root cellar?

In "She of Little Faith", when evil rears its ugly head, how does Ned Flanders know to take the boys down to the root cellar?

A-Dial-A-Prayer calls him
B-His Satan-sense tingles
C-His doorknobs turn red hot

Hightlight for answer: B-His Satan-sense tingles