If devils exist, their first aim is to give you an anesthetic -- to put you off your guard. Only if that fails, do you become aware of them.
C. S. Lewis (2014). “God in the Dock”, p.46, Wm. B. Eerdmans Publishing

If devils exist, their first aim is to give you an anesthetic -- to put you off your guard. Only if that fails, do you become aware of them.