Command 9&10 Do Not Envy

St Augustine on Catechizing the Uninstructed, Blog 2

If you seek to become a Christian for social or temporal reasons you may backslide from the faith when you see “wicked and impious men” who are more prosperous than you are.  You may ask yourself, How is this faith helping me?  This is the wrong question, for the true Christian seeks “everlasting blessedness and the perpetual rest of the saints so he may not pass into eternal fire with the devil but rather enter into the Eternal Kingdom together with Christ.  He will be on his guard in every temptation, so we will neither be corrupted by prosperity nor be utterly broken in spirit by adversity, but remain modest and temperate during good times, and be brave and patient during times of tribulation.”  Then this Christian will “Love God more than he fears hell,” and he will recoil from evil thoughts and temptations. […]

Catholic Catechism

Catholic Catechism, Do Not Covet, CCC 2214-2216

Surprisingly, the Catholic Catechism discusses concupiscence not when reflecting on the commandment prohibiting adultery but on the commandment forbidding coveting your neighbor’s wife.  Concupiscence is not itself a sin, and although it is commonly thought of as a sexual sin, it can “refer to any intense form of human desire.”  “Concupiscence stems from the disobedience of the first sin.  It unsettles man’s moral faculties and, without being in itself an offense, inclines man to commit sins.” The Catholic Catechism footnotes the decrees of the Council of Trent, which teaches that “concupiscence or the tinder of sin remains in the baptized.  Since it is left for us to wrestle with, it cannot harm those who do not consent but manfully resist it by the grace of Jesus Christ.”  This decree of Trent then confirms that concupiscence is not sin itself, but inclines us to sin. […]