Ambrose of Milan

Fools then are not free, for it is said to them, Be ye not like to horse and mule, which have no understanding, whose mouths must be held with bit and bridle lest they fall upon thee. Great plagues remain for the ungodly; for they have need of these, in order that their folly may be restrained. It is good discipline which requires this, not severity. Further, he that spareth his rod hateth his son: for a man's own sins scourge him still more severely. For heavy is the weight of crime, heavy the scourges of sin; they are heavy as a sore burthen, they inflict wounds upon the soul, and make the ulcers of the mind to stink.