Envy

148. Envy is a sadness arising from the contemplation of our neighbour's welfare, when we imagine that the good which happens to him must be to our own detriment, prejudicial to our own glory and interest; but of his goods we only envy those which bring us esteem in the eyes of the world-----riches, dignity, the friendship and favours of the great, science, praise, fame, and all that which seems to us to contribute to our credit and to bring us honour.
And it is thus that envy is born within us, when we see one who is richer, more learned than we are, another wiser and more virtuous than we, another who has more talent and ability, and whom therefore we should like to see deprived of these gifts in order that he might also be deprived of the praise and honour and any other advantages which we imagine are more due to us than to him. Now the sin consists in this: that when we ought, from a sense of charity, to rejoice at our neighbour's prosperity, we are only saddened at it, wishing in our pride that it. might be ours, in order that we might be superior to our neighbour in merit; and this sin is the especial sin of the devil, as the Wise Man says, "the envy of the devil," [Wisd. ii, 24] and therefore the Holy Ghost most justly commands us through St. Paul to guard against it: "Let us not be envying one another," [Gal. v, 26] as it is easy to sin mortally in one way or another. But nevertheless, how common this vice is in families, in communities, in every state of life, to high and low, rich and poor, to seculars and even to the Religious themselves!
All this evil proceeds from a false conscience, which leads us to believe that envy is not a great sin, and therefore, although it be a grievous evil, it is neither feared, nor avoided, nor do we study to amend ourselves of it. This reflection is from St. Cyprian: "Envy seems a small offense, so that, whilst it seems slight to us, it is not feared; whilst it is not feared, it is despised; whilst it is despised, it is not easily avoided, and thus becomes a secret source of ruin." [See [St. Thomas, 2a 2æ, qu. xxxiv, art. 6; et qu. xvi, art. 1 et 2 etc.; et qu. clviii, art. 11 et 14]