Sleeping Alone

Hello Is it an issue sleeping alone in a house at night if there are other houses next to the house one is sleeping in? And is it enough to leave a light on in the house even if there will be no light in the room one is sleeping in?

Shalom!

Thank you for your question.

The source for the concern on sleeping alone finds itself in the Gemara, Shabbat 151b, where it says, “Rav Chanina said: It is forbidden for one to sleep alone in a house. Whoever sleeps alone in a house will be seized by Lilith.” (Lilith is a female demon). This teaching found its way into both ethical and halachic works such as the Orchos Chaim 59 and the Mishna Berura 239:9.

According to most interpretations, the concern only applies at night, though interestingly, you mention a possible distinction when “there are other houses next to the house one is sleeping in.” According to those who forbid sleeping alone even during the day (for example Zohar, Tazria, 45a), even they would allow it if there are other homes in the area. So once, again, we see there is essentially no concern nowadays at all for sleeping alone during the day.

The Mishna Berura recommends that one who sleeps alone in a room should leave the door slightly open. But this only helps when there are others in the house. One who must sleep alone in a house with no one else present should leave a light on the room. This is based on the teaching from Berachot 43b that a fire/light is the same as having another person present.

All of the above (day/night) only applies when there is no light from the outside shining in. Even moonlight would suffice for this purpose (Kaf Hachaim, OC 239:17).

The ban on sleeping alone applies equally to men and women (Shaar Hatzion 339:17). It does not apply in a Sukka where there is a constant mitzva being performed.