29 The exercise or indulgence of the bodily appetites is intended to secure the continued existence and the invigoration of the individual or of the species. If the appetites go beyond this, and carry the man, no longer master of himself, beyond the limits of temperance, they become unlawful and shameful lusts, which severe discipline must subdue. But if this unbridled course ends in plunging the man into such a depth of evil habits that he supposes that there will be no punishment of his sinful passions, and so refuses the wholesome discipline of confession and repentance by which he might be rescued; or, from a still worse insensibility, justifies his own indulgences in profane opposition to the eternal law of Providence; and if he dies in this state, that unerring law sentences him now not to correction, but to damnation.
Source: Reply to Faustus the Manichaean (New Advent)