A cowardly cur barks more fiercely than it bites.
Fear makes men believe the worst.
Doctors cure the more serious diseases with harsh remedies. Curtius Medici graviores morbos asperis remediis curant
Nothing is strong that may not be endangered even by the weak.
Nothing is so secure in its position as not to be in danger from the attack even of the weak.
Habit is stronger than nature.