Q. 1. Is it possible to sin during one's dreams? Sometimes I wake up and remember an impure dream that I had. I feel terrible about it and do not know how to stop such dreams from occurring. Can you help me with this matter?
A. 1. Regarding sinful dreams, it is important to remember that three conditions must be met before it can be said that one committed a sin. Those conditions are:
1. It must be of a grave matter;
2. It must be committed with full knowledge that it is a mortal sin;
3. It must be committed with full consent. (Catechism of the Catholic Church # 1857)
Condition # 2 & 3 above cannot be met in dreams. Therefore, one cannot be sinning during dreams.
When one dreams, he has no control over his unconsciousness. So he cannot consent (# 3). Nor does he have the ability to discern if his thoughts are sinful or not (# 2).
Can one stop such dreams from happening? It depends if the individual is doing something that may lead to sinful dreams. Some people remember vividly their dreams after eating rich foods prior to bedtime. Dreams can also result from poor indigestion. Those who entertain pornography prior to their bedtime have been known to have dreams of a sexual nature. Entertaining pornography means reading erotic material, viewing nude pictures, participating in adult chat rooms, with or without webcams.
The individual sins when he entertains pornography, during which time the three aforementioned conditions of sinning are met. The dreams that follow, they being consequences of sinful actions, dreams which cannot be controlled by the consciousness, are not sinful.