Quodlibet 32 – Theological and Cardinal Virtues
The activities that stem from a person’s habits may be either good or bad – they may be activities that direct a person either towards or away from their fulfilment and happiness. This view of morality is not to be confused with utilitarianism which seeks pleasure and avoids pain. The virtuous life is centred on joy which is rooted in truth and is communicable to others, and although pleasure may go together with joy, it is also possible to be joyful whilst one undergoes great trials. The morally virtuous person will have acquired a variety of habits which enable them to habitually perform morally good acts, and the chief of these habits are the cardinal virtues: temperance, courage, justice, and prudence. For example, with enough effort, a person who lacks the virtue of courage may grow to be courageous and love acting courageously if they are rewarded for performing courageous acts and criticized for performing cowardly acts.
Temperance is love giving itself entirely to the beloved; courage is love readily bearing all things for the sake of the beloved; justice is love serving only the beloved and therefore ruling rightly; prudence is love distinguishing wisely between what hinders it and what helps it (from De moribus ecclesiae catholicae)
From a purely natural point of view, Jesus´ teaching in the Sermon on the Mount is impossible to follow. Naturally, people who mourn or who are persecuted are not happy. But Christ puts us in direct contact with God so that we are raised above our human nature and so are genuinely able to follow his teaching. With the theological virtues of faith, hope and charity, we become capable of performing acts of temperance, courage, justice and prudence which are infused with a quality of holiness.