“ENVY is specifically opposed to the joy of charity insofar as it relates to one’s neighbor. For although there are many ways in which we can feel sadness about another’s good (as the Philosopher observes in 2 Rhetoric, 9, 1386b), envy is the special sadness caused when another’s good exceeds mine and results in inequality. Thus it most formally looks to the neighbor’s good insofar as he is similar to me. It regards the good of another as the diminishment of my own good, not as if it actually took away what is mine (that would elicit fear rather than envy) but precisely because the other’s increases and is no longer equal to mine, diminishing my good only relatively. Envy exists between similar and equal persons and pertains to pusillanimity or smallness of soul in the one who, unable to increase his own glory, wants that of another to decrease to the level of his. Of itself it is a mortal and sin because its motive, one's own glory, is most desirable and causes many other things to be sought and avoided.” (See S.T. II-II, q. 36.)
~John of St. Thomas: Introduction to the Summa Theologiae of Thomas Aquinas.
No. 48, The Seven Vices: Envy, by Giotto di Bondone.
Fresco, A.D. 1306; Cappella Scrovegni (Arena Chapel), Padua.
