"But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart."
I had a companion on my mission with Obsessive-Compulsive Disorder (OCD). I'd mostly associated OCD with excessive handwashing and similar behaviors, but found out that, as is the case with most mental illness, pop culture stereotypes aren't a terribly helpful source of information.
For my companion, at least, OCD mostly meant not being able to ignore or throw out the random thoughts most of us barely even register when they pass through our heads. That is, he might have passing sexual or violent thoughts, and although he would never have acted on them, he couldn't let go. He'd freak out about them and they'd get stuck in his head until he could barely function. That he was serving a mission, in particular, made it difficult for him: his thoughts made him feel out of place, unworthy, and as if he'd actually committed sin.
Matthew 5: 28 was a particular source of difficulty for him. He sometimes told me that when sexual thoughts got stuck in his head, he felt that he was guilty of adultery according to this verse.
I told him I believed that the verse referred not simply to sexual thoughts, but to the specific decision to endorse them. That the Lord here is saying that we will be accountable for every woman we would have slept with, even when the opportunity to actually break the law of chastity never presents itself. His thoughts, I argued, could not count because they didn't constitute a moral decision: they were simply images and unsought impulses, not a chosen course of desired action. The Higher Law was perhaps not so strict as he imagined it.
Looking back, I don't think that's the best reading for everyone. For some, the verse is probably better read as a prohibition on pornography. For others, the verse ought to be read more as a warning against investing too much intimacy of any kind outside of marriage. But for an OCD missionary, I think the reading I gave makes a lot of practical sense.
How can we give people a range of readings so that the spirit can help them find the one(s) most relevant to their situation?