Certain actions are forbidden, and the doers of them are subjected to some painful infliction; which is increased in severity if they are persisted in.

Now, what would be the natural consequence of such a system, under the known laws of feeling, will, and intellect?
Would not an action that always brings down punishment be associated with the pain and the dread of punishment?
Such an association is inevitably formed, and becomes at least a part, and a very important part, of the sense of duty; nay, it would of itself, after a certain amount of repetition, be adequate to restrain for ever the performance of the action, thus attaining the end of morality.
There may be various ways of evoking and forming the moral sentiment, but the one way most commonly trusted to, and never altogether dispensed with, is the associating of pain, that is, punishment, with the actions that are disallowed.

Punishment is held out as the consequence of performing certain actions; every individual is made to taste of it; its infliction is one of the most familiar occurrences of every-day life.

Consequently, whatever else may be present in the moral sentiment, this fact of the connexion of pain with forbidden actions must enter into it with an overpowering prominence.

Any natural or primitive impulse in the direction of duty must be very marked and apparent, in order to divide with this communicated bias the direction of our conduct.