Hirhur

From Halachipedia
  1. It is strictly forbidden to have an inappropriate thought about doing a sin of immorality. Doing such violates the Biblical command of "לא תתורו אחרי לבבכם ואחרי עיניכם", "Don't stray after your heart and eyes"[1], which Chazal explain to mean that it is forbidden to have thoughts about doing sins of idolatry and immorality. This prohibition applies equally to men and women. [2]
  2. There is an additional prohibition for a man to think inappropriate thoughts, even about his wife when she is tahor[3], as it can lead to bitul zera. This too is a Biblical prohibition based on the pasuk "נִשְׁמַרְתָּ מִכֹּל דָּבָר רָע"[4], which Chazal interpret as saying that it is forbidden to have an inappropriate thought during the day since it will lead to bitul zera by night.[5] This only applies to men and not women.[6]
    1. As a consequence of the prohibition to think inappropriate thoughts it is forbidden to look at inappropriately dressed women.[7] See Inappropriate_Staring_at_the_Opposite_Gender.

Sources

  1. Bamidbar 15:39
  2. Sefer Hachinuch (Mitzvah 387), Rambam (Lavin 47), Igrot Moshe EH 1:69
  3. Igrot Moshe EH 1:69
  4. Devarim 23:10
  5. Ketubot 46a, Rambam (Isurei Biyah 21:21), Igrot Moshe EH 1:56
  6. Igrot Moshe EH 1:69
  7. Ketubot 46a, Rambam (Isurei Biyah 21:21), Igrot Moshe EH 1:56