The following is from the "Doeihu | Daily Halacha" email series
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Shemiras Einayim - Part 1
Below is a short overview of the halachos of shemiras einayim.

1. It is forbidden for a man to gaze at a woman. One who does so transgresses the prohibition of “V’nishmarta mikol davar ra, you must guard yourself from every improper thing” (Devarim 23:10). In many instances, he also transgresses the prohibition of “Lo sasuru acharei levavchem v’acharei eineichem, you may not turn after your hearts and after your eyes” (Bamidbar 15:39). (Berachos 61a; Shulchan Aruch EH 21:1 and OC 75; Mishnah Berurah 75:17)
2. According to the letter of the law, if one merely glances a woman incidentally, without intention to gaze at her, he has not transgressed any prohibition. (The poskim write that the prohibition against looking at a woman only applies when one gazes at her, i.e., while concentrating and analyzing her features. However, if one merely glances at a woman superficially, without analyzing details or focusing on what she looks like, this is permitted according to the letter of the law. It is possible for one to know of the other person’s features after glancing at them many times. However, in this case, knowing the features is the result of glancing, rather than gazing.) (Yam Shel Shlomo, Kesubos ch. 2; Pri Megadim MZ 76:1; Mishnah Berurah 76:7; Igros Moshe OC 1:40; see Chut Shani EH p. 42)
3. From a mussar perspective, however, a man should avoid even glancing at a woman, certainly when that could lead to improper thoughts. (Mishnah Berurah 75:1 and :7; see Chut Shani EH p. 42)

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Shemiras Einayim - Part 2

D. Furthermore, an “adam chashuv” should act stringently and refrain from even “glancing” at women. (ibid.)
E. It is forbidden to “glance,” and certainly to gaze, at any part of a woman’s body that is normally covered. It is certainly forbidden to even glance at a woman who is dressed immodestly. (Mishnah Berurah 75:1 and :7; Igros Moshe OC 1:40 and EH 3:13; see Chut Shani EH p. 42)
F. Women also must guard their eyes to avoid gazing at inappropriate things. In certain cases, there is an issur d’Oraysa for a woman to Gaze at men or at indecent things, just as there is for men (as discussed at length in previous emails). (Sefer Hachinuch, Mitzvah 363; Shevet Halevi vol. 5, 197:2, Igros Moshe EH 1:69; Chut Shani EH p. 43; Shu”t Az Nidberu 12:39; see Shu”t Be’er Moshe vol. 4, 147:23)
G. If a person saw a forbidden sight inadvertently, it is not considered an aveirah; however, he must look away immediately. (See Tur OC 1:1)

Shemiras Einayim on a Screen

1. All of the halachos of shemiras einayim also apply to sights that one sees in pictures, on a video, etc. What a person is forbidden to gaze or glance at in real life is also forbidden to be viewed on a screen. (Shevet Halevi 2:2; Minchas Yitzchok vol. 2, 84:9; see also Shu”t Divrei Malkiel 3:58; Rav Berachos by the Ben Ish Chai, maarechesTzadi; Shu”t Be’er Moshe vol. 3, 154 and vol. 4, 147:21; Shu”t Emek Hateshuvah 96:34; Yisrael Kedoshim 86)

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Seeing pictures or watching videos on a screen can be even worse than seeing things in real life.

• The poskim say (see Minchas Shlomo 91:23) that one reason for the very strict prohibition of walking behind a woman — “achorei ishah” — is because when one stands face-to-face, there is a natural sense of embarrassment to stare directly at the other person; therefore, one will usually refrain from doing so. On the other hand, when someone is behind someone else, the person in front won’t realize if the person behind them is staring at them and the person in back will lack the natural tendency to look away. The same logic applies to looking at images in a picture or on a screen. One who views such images does not have the natural embarrassment that stops him from looking at the woman that he sees.

• The poskim also explain (see Chazon Ish OC 16:7) that the reason it is forbidden to even glance at an immodestly dressed woman, even without “gazing” at her, is because even just glancing can lead a person to intentionally gaze at them. The same applies to pictures, and all the more so to videos, which naturally attract a person’s attention and cause him to gaze at them. One who watches a video is even drawn to look at things which, were he to see them in real life, he would merely glance at them and immediately look away or continue on his way. Therefore, this concept — that merely glancing at inappropriate things leads to deliberately gazing at them — certainly applies to images on a screen.

Thoughts

1. It is forbidden for a man or woman to think sinful or inappropriate thoughts about a member of the opposite gender. If one consciously does think such thoughts, he or she transgresses the prohibition of “Lo sasuru acharei levavchem v’acharei eineichem, you shall not turn after your hearts and after your eyes.” (Berachos 12b; Shulchan Aruch EH 23:2 and 25:1; Igros Moshe EH 1:69)

1. Similarly, it is forbidden for a man to think any thoughts that could lead him to pitfalls. If he does think such thoughts, he transgresses the prohibition of “V’nishmarta mikol davar ra, you shall guard yourself from every improper thing.” (Shulchan Aruch EH 21:1, 23:3, and 25:1; Bais Shmuel ibid:2)

Thoughts Part 2

C. Included in this prohibition is the rule that one is forbidden to do any type of action that could lead him to have improper thoughts. If a person knows that doing a certain thing or going to a certain place will lead him to have such thoughts, he may not do so. (Sefer Hachinuch, mitzvah 188; see also Shulchan Aruch EH 21:1, 23:3, and 25:1; Chut Shani EH 21:7; Igros Moshe EH 1:69)

D. If an improper thought enters a person’s mind unintentionally, it is not considered an aveirah. However, he should immediately divert his thoughts elsewhere in order to stop thinking the inappropriate thoughts. (Ezer M’Kodesh EH 23:3; Derech Pikudecha, mitzvah 35, see also Rabbeinu Bechayei, Devarim 29:18)

Darka Acharina

Below is a short overview of the halachos of “darka acharina” (problematic situations where another option exists), which were discussed at length in previous emails:

1. As mentioned in the past, it is forbidden for a person to place himself in a situation where he knows that he will be faced with spiritual challenges. Chazal (Bava Basra 57b) give the example of a person who has to travel to a certain location and can choose one of two roads to get there. On one of the routes, he will be exposed to forbidden sights (e.g., there are immodestly dressed women), whereas the other is free of temptation. If the person chooses to take the road which poses spiritual challenges, he is referred to as a rasha.
2. If there is no other road to his destination (or no other way to do the specific thing he needs to do), he is permitted to take that road; however, he must be very careful to guard his eyes and thoughts in order to avoid seeing or thinking anything forbidden. (Rashbam, Bava Basra 57b; Shu”t Az Nidberu 6:75; Chut Shani EH page ; Shu”t Meishiv Nevonim 6:48)

When there is No Other Option

C. Even when no other option exists, one is only permitted to take the road that presents spiritual challenges if he is confident in himself and knows that he can guard his eyes and thoughts from sin. However, if he knows for certain that he is not strong enough to withstand the temptation and he will look at forbidden sights or think forbidden thoughts, or even if there is a larger probability that he will transgress than not, it is forbidden for him to take that road even though there is no other option. (Sefer Hachinuch, mitzvah 188; Igros Moshe 1:56; Chut Shani EH 21:5; Yisrael Kedoshimperek 4)

Similarly, the poskim write that it is only permitted to pass through a road that contains spiritual challenges (such as immodestly dressed women) if one is simply traveling through the area and there is no other way to reach his destination. It is never permitted to position oneself in a setting that contains such challenges. Therefore, for instance, it is prohibited to go to and loiter at a place frequented by immodestly dressed women. One who goes to such a place is called a rasha (See Shu”t Vayaan Dovid 6:15 quoting Rav Shmuel Wosner zt”l; see also Shu”t Yechaveh Daas 5:63)

The Prohibition of “Lo Savi So’eivah el Beisecha”

Below are the halachos that relate to the prohibition of “Lo savi so’eivah el beisecha, you shall not bring an abomination into your home” (Devarim 7:26).

A. It is forbidden to bring anything that is considered a to’eivah (abomination) into one’s domain. This includes possessing any written material or images that contain idolatry or heretical ideas. Furthermore, one may not possess books, magazines, or catalogues that are specifically intended for immorality or immodesty. If one does bring such things into his possession, even if he does not look at the pictures or use these things for improper purposes, he transgresses this prohibition. (Sefer HaChinuch, mitzvah 429; Rema OC 90:23; Taz, Gra, and Mishnah Berurah ad loc.; Kovetz Maamarim of Rav Elchonon Wasserman zt”l, p. 27)

B. The Shulchan Aruch rules that one may not daven while in the proximity of items that are in the category of “to’eivah.” (Rema and commentaries ibid.)

Arousing the Yetzer Hara

There is a prohibition to arouse one’s yetzer hara.
This means that one may not do things that arouse his desire to sin.
(Shulchan Aruch OC 307:16; Mishnah Berurah :59; Derech Pikudecha, mitzvas asei 53)

Profanity - Part 1

 Below is a brief review of the laws of nivul peh, inappropriate language.

1. It is forbidden to speak words of nivul peh. (Kesubos 8a; Shabbos 33a; Rishonim ad loc.; Charedim 24:49; Shulchan Aruch OC 407:16 and EH 25:1)
2. The prohibition against speaking nivul peh is not limited to inappropriate language. It also dictates that the topics a person speaks about must be refined. (ibid.; see also Pele Yoetz, erech Dibbur)

Profanity - Part 2

3. Even if someone uses refined words, if it is evident that he is hinting to vulgar things or immodest matters, he has violated the prohibition against speaking nivul peh. (ibid.)

4.It is similarly forbidden to listen to, read, or write vulgarities. (ibid.)

5. Chazal use very strong terms when discussing this prohibition and say that the sin of nivul peh is the cause of many misfortunes. (Shabbos 33a; Kesubos 8b)