Shulchan Aruch (Yoreh De’ah 195:7): “One may not look (yistakel) even at her heel, and not at covered areas [yet it is permitted to look at revealed places, even though one derives benefit].”
1-Why does the Beis Yosef use the loshen לא יסתכל? This seems to imply that only staring/concentrating is prohibited while a glance is not.
2-The Rama states: אבל מותר להסתכל בה במקומות הגלוים אע”פ שנהנה בראייתה. Are we not concerned that this could be come a problem?
1. It is true that Magen Avraham writes in two places that histaklus implies gazing rather than merely seeing (125:35 concerning seeing the kohanim, and 225:20 concerning looking at a wicked person), but Mishnah Berurah writes (75:7, quoting from Peri Megadim) that concerning seeing an ervah, one must avoid seeing, and not only staring or gazing. It is possible, however, that concerning one’s wife, which is what the Shulchan Aruch (Yoreh De’ah 195) is referring to, the prohibition applies onto to gazing, and not to merely seeing, and this is also implied by the Beis Shmuel (21:7), who refers to “habatah” (gazing). However, it is very hard to distinguish between seeing and gazing, and although one does not transgress a prohibition by inadvertent sight, one should therefore refrain even from seeing covered areas.
2. Because the halachah refers to one’s wife, who will be permitted after the end of the niddah period, we are not concerned that deriving benefit from revealed parts of the body will lead to transgression.