Knowledge without repentance

"Some bless themselves that they have a stock of knowledge, but what is knowledge good for without repentance? It is better to mortify one sin that to understand all mysteries. Impure speculatists do but resemble Satan transformed into an angel of light. Learning and a bad heart is like a fair face with a cancer in the breast. Knowledge without repentance will be but a torch to light men to hell."

From The Doctrine of Repentance, by Thomas Watson.