We are continuing with sins of the tongue.
Citing the Summa Theologica of St. Thomas Aquinas, we have already discussed reviling (contumely), backbiting (detraction), and talebearing (whispering).

Today we continue with derision (mockery).  St Thomas presents derision in II-II, Q. 75, (2 art.)

Whether derision is a special sin distinct from those already mentioned?
In preface to his answer, St Thomas observes that derision is done in jest or to make fun while contumely, detraction, and talebearing are all done in seriousness and not in jest.

Also, St. Thomas reminds us that sins of speech are to be weighed mainly by the intention of the speaker.  Regarding sins of the tongue, we must observe not just what is said but why it is said.

Therefore, we take notice that the reviler, in speaking evil to another openly, intends to dishonor the person he reviles, and the backbiter, in speaking evil of another in secret, intends to degrade a man’s good name, and the talebearer, in speaking evil to another, intends to ruin the friendship he has with the person spoken ill of, so the derider, by his mocking speech, intends to shame the person he derides.

St Thomas concludes that as shaming is a distinct end from the other sins of the tongue, so derision is a distinct sin of the tongue.

But someone may claim that mockery is not a specific sin of the tongue as the injury of derision affects either a person’s honor, his good name, or damages his friendships with others, and, therefore, for this reason it seems derision is not a distinct sin.

In answering this person, St Thomas points out that a secure and calm conscience is a great good.  “A secure mind is like a continual feast.” (Pr 15:15) Wherefore, he who disturbs another man’s conscience by confounding him inflicts a special injury on him, namely making one ashamed,  hence, derision is a special kind of sin. 

Nor is shaming the same as being dishonored.  St Thomas follows St Damascene is distinguishing the two: to dishonor is to remove due honor; to shame (or be ashamed) is to fear dishonor.

Whether derision can be a mortal sin?
St Thomas tells us that the object of derision is always some evil or defect. 

When an evil is great it is no laughing matter, not a matter of jest, but taken with seriousness.    Thus if a matter is taken in jest or turned to ridicule it means that the matter is thought slight.

St Thomas tells us that an evil may be considered slight in two ways.  First, in itself; second, in relation to the person. 
 Whenever someone makes fun of another person’s evil or defect, because it is slight evil in itself, this is a venial sin by reason of it being a slight evil.  On the other hand, this defect may be considered as a slight evil in relation to the person “just as we are wont to think little of the defects of children and imbeciles.” 

Making fun of a person not because his defect is slight in itself but because it is slight in relation to him is, St Thomas says, “to scorn him altogether, and to think him so despicable that his misfortune troubles us not one whit, but is held up as an object of derision.”  This is the type of derision which is a mortal sin, more grievous than reviling, which is also done openly.  For whereas the reviler seems to take another’s evil seriously, he who derides does so in fun and for this reason seems more to despise and dishonor him.  In this sense, derision is a grievous sin and more grievous as a greater respect is due the person derided.

Of all persons, it is most grievous to deride God.  “Whom hast thou reproached, and whom hast thou blasphemed, and against whom hast thou exalted thy voice?”  Isaiah responds, “against the Holy One of Israel.” (Is 37:23)

Next, it is grievous to mock or make fun of one’s parents.  “The eye that mocks his father and that despises the labor of his mother in bearing him, let the ravens of the brooks pick it out, and the young eagles eat it.”  (Pr. 30:17) 

Next, it is grievous to mock good persons because honor is the reward of virtue and so we read in Job 12:4, “the simplicity of the just man is laughed to scorn.”  St. Thomas tells us that derision given good men does great harm.   For it turns men away from doing good deeds as St Gregory states, “Who when they perceive any good points appearing in the acts of others, directly pluck them up with the hand of a mischievous reviling.”

Now that is a summary of St. Thomas on derision.

On St. Thomas’ last point, the making fun of good persons... I have a story.
There was once a boy, 12 or so, who one day made the determination “I want to be a good boy; I want to be a saint!”  And so he set about to say his daily prayers with greater regularity, and to help around the house with greater zeal and less complaint; he was obedient and careful not to criticize or use bad language; he would even correct his friends or brothers if they did sinful things.  Well, this went on for a month... and more and more it got out that he had changed.  At first his brothers took umbrage and called him “goody-two-shoes” then the neighborhood boys picked this up so they too called him “goody-two-shoes”, or “the angel.”  Such making fun wore down the lad... and, after another month, he deserted his cause.

May we always encourage one another by our whole manner of life; by what we do but also by what we say.

Holy scripture records, “a peaceable tongue is a tree of life.”  By the speech of our tongue, we can give life; by the same, however, we can also take it away.