Can we sin via our dreams? - If your conscience is uneasy about this matter, I would suggest to you to be rather too severe than too lenient with yourself.
Pursuing this harsh line in setting the matter straight, I would firstly presume that no dream falls from the sky into the head of the person dreaming at night but can only arise because it is already preconditioned in the person’s experiences and expectations. One must not drive the issue as far as Freud in saying that every image of a dream is a secret or openly recognizable realization of a certain desire(and one certainly must not try to be as ridiculous as he preferred to appear in claiming that every such desire is rooted in sexuality). But it is mere common sense to ascertain that a dream often goes in advance of our expectations, that it only amplifies and distorts a kind of material already present in the mind, in the neural patterns, and that it thus bears ressemblance to our own psychic makeup. Indeed, it would be Jungian to believe that dreams could stand in no relation with our ego-consciousness and assault the ‘I’ like some altogether unimaginable dark force. - Someone who has never been in Paris and never heard of Paris simply won’t dream of being in Paris, of visiting the Louvre or the Eiffel Tower. And someone whose saintly mind is completely detached from all those base sentiments of human resentment certainly would be quite unable to dream of himself beating somebody else up, or else wouldn’t dream in any other way about it than in the way of an exasperating nightmare.
As a sidenote: I’m a strong believer in the influence of eating habits on dream patterns. For instance, after a family feast(in other words: after an evening of gluttony) when I go to bed with my stomach still rumbling loudly, dreams tend to be more prolific.
Taken as much into consideration, I’d propose you should choose light articles of food in the afternoon and try to abstain from both eating and drinking after, say 4 p.m. Let’s see if you won’t find that the frequency of your dreams is in prospect of declining. Of course, this sounds very much like deprivation, and I would only recommend it if the suffering from nightmares really was untenable. But perhaps it’s worth the try.