Sfeka d'yoma

Sfeka d'yoma (Talmudic Aramaic: ספיקא דיומא, lit. "doubt about the day",^[1] or doubt regarding the exact date of the day^[2]) is a concept and legal principle in Jewish law^[3] which explains why some Jewish holidays are celebrated for one day in the Land of Israel but for two days outside the Land.^[1]^[4] The implications of sfeka d'yoma are discussed in Rosh Hashanah 21a and in the commentaries and poskim.^[5]

^ ^a ^b "Old Traditions For A New Year". Baltimore Jewish Times. 30 May 2013. Retrieved 4 December 2013.
^ "GLOSSARY / DEFINITIONS / SPELLING". HaY'Did Learning Center. Retrieved 5 December 2013.
^ היים גוסף דביד אזולי, דוד בן משה אביטן (1774). ספר ברכי יוסף: אורח חיים.
^ Laifer, Rabbi Usher. ""Chag HaShavuos" – A Holiday of Preparation". Yeshiva Gedolah of Greater Washington. Retrieved 1 November 2013.^{[dead link]}
^ Feldman, Rabbi Pesach. "Outlines of Halachos from the Daf: Rosh Hashanah 21". dafyomi.co.il. Retrieved 5 December 2013.

[balt-1] "Old Traditions For A New Year". Baltimore Jewish Times. 30 May 2013. Retrieved 4 December 2013.

[2] "GLOSSARY / DEFINITIONS / SPELLING". HaY'Did Learning Center. Retrieved 5 December 2013.

[3] היים גוסף דביד אזולי, דוד בן משה אביטן (1774). ספר ברכי יוסף: אורח חיים.

[shavuos-4] Laifer, Rabbi Usher. ""Chag HaShavuos" – A Holiday of Preparation". Yeshiva Gedolah of Greater Washington. Retrieved 1 November 2013.^{[dead link]}

[5] Feldman, Rabbi Pesach. "Outlines of Halachos from the Daf: Rosh Hashanah 21". dafyomi.co.il. Retrieved 5 December 2013.

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