2515 Etymologically, "concupiscence" can refer to any intense form of human desire. Christian theology has given it a particular meaning: the movement of the sensitive appetite contrary to the operation of the human reason. The apostle St. Paul identifies it with the rebellion of the "flesh" against the "spirit." 302 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. 303
Notes:
302 Cf. Gal 5:16, 17, 24; Eph 2:3.303 Cf. Gen 3:11; Council of Trent: DS 1515.