16,374
edits
Reference of Measurements in Halacha: Difference between revisions
From Halachipedia
Reference of Measurements in Halacha (view source)
Revision as of 16:32, 6 August 2012
, 6 August 2012no edit summary
No edit summary |
No edit summary |
||
| Line 1: | Line 1: | ||
==Kezayit== | ==Kezayit== | ||
# According to Ashkenazim, all sizes are measured in volume and not weight. <Ref> Mishna Brurah 456:3, Vezot HaBracha (pg 6) </ref>However, according to Sephardim the actual halacha is that measures are in volume but the minhag is to follow the measures in weight. <ref>See Yalkut Yosef (Klalei Brachot pg 195-202) discusses this at length. </ref> | # According to Ashkenazim, all sizes are measured in volume and not weight.<Ref> Mishna Brurah 456:3, Vezot HaBracha (pg 6) </ref> However, according to Sephardim the actual halacha is that measures are in volume but the minhag is to follow the measures in weight. <ref>See Yalkut Yosef (Klalei Brachot pg 195-202) discusses this at length. </ref> | ||
# There’s a dispute in the Rishonim whether the [[Kezayit]] (olive size) is a half or third of a KeBeytzah (egg size), and regarding Bracha Achrona and Deoritta Mitzvot, the halacha follows the opinion that a Kezayit is half a KeBeytzah. <Ref> | # There’s a dispute in the Rishonim whether the [[Kezayit]] (olive size) is a half or third of a KeBeytzah (egg size), and regarding Bracha Achrona and Deoritta Mitzvot, the halacha follows the opinion that a Kezayit is half a KeBeytzah. <Ref> | ||
* Mishna Brurah 486:1 writes that the Tosfot holds a kezayit is half of a KeBeitzah with the shell and the Rambam holds it is a third of a KeBeitzah (see Tosfot (Yoma 80b D”H Agav), Rambam (Eiruvin 1:9)). S”A 486 rules like Tosfot. Rav Avraham Chaim Noeh (Shiurei Torah 3:12) argues that Tosfot holds half a KeBeitzah without the shell. | * Mishna Brurah 486:1 writes that the Tosfot holds a kezayit is half of a KeBeitzah with the shell and the Rambam holds it is a third of a KeBeitzah (see Tosfot (Yoma 80b D”H Agav), Rambam (Eiruvin 1:9)). S”A 486 rules like Tosfot. Rav Avraham Chaim Noeh (Shiurei Torah 3:12) argues that Tosfot holds half a KeBeitzah without the shell. | ||
| Line 61: | Line 61: | ||
==Ben HaShemashot== | ==Ben HaShemashot== | ||
# Ben HaShemashot is the time period between certain daytime and certain nighttime. In many halachot, it is considered a doubt whether it is considered day or night and has many practical ramifications. There is a major dispute how long this period is. <ref> | # Ben HaShemashot is the time period between certain daytime and certain nighttime. In many halachot, it is considered a doubt whether it is considered day or night and has many practical ramifications. There is a major dispute how long this period is. <ref> | ||
* Gemara Shabbat 34b says Ben HaShemashot is considered as a doubt whether it is considered daytime or nighttime. When is Ben HaShemashot? Rabbi Yehuda says that Ben HaShemashot starts from Shekiyah and concludes when the entire ball of the sun has set. Rabbi Yose, however, says that Ben HaShemashot is as short as the blink of an eye. | * '''Gemara Shabbat''' 34b says Ben HaShemashot is considered as a doubt whether it is considered daytime or nighttime. When is Ben HaShemashot? Rabbi Yehuda says that Ben HaShemashot starts from Shekiyah and concludes when the entire ball of the sun has set. Rabbi Yose, however, says that Ben HaShemashot is as short as the blink of an eye. | ||
* '''Explanation of Rabbi Yehuda's opinion:''' Rabba explains Rabbi Yehuda as saying that Ben HaShemashot starts from Shekiyah even though the sky is still red, while Rav Yosef says Ben HaShemashot starts from when the bottom of the sun already set. It follows, says the Gemara, that according to Rabba the span of Ben HaShemashot is ¾ of a mil and according to Rav Yosef Ben HaShemashot is 2/3 of a mil. | * '''Explanation of Rabbi Yehuda's opinion:''' Rabba explains Rabbi Yehuda as saying that Ben HaShemashot starts from Shekiyah even though the sky is still red, while Rav Yosef says Ben HaShemashot starts from when the bottom of the sun already set. It follows, says the Gemara, that according to Rabba the span of Ben HaShemashot is ¾ of a mil and according to Rav Yosef Ben HaShemashot is 2/3 of a mil. | ||
* The Rif (15a) writes that since it is unclear whether halacha follows Rav Yosef or Rabba, one should be strict to follow Rabba that Ben HaShemashot begins at Shekiyah. Then he says that it seems halacha should follow Rabba because halacha always follows Rabba with three exceptions and this isn't one of them. Similarly, Rambam (Shabbat 5:4) rules like Rabba that Ben HaShemashot begins at Shekiyah. Rabbenu Yonah (quoted by Rosh Shabbat 2:23) argues that since they're not arguing about which logic is correct but about what Rav Yehuda said (see Gemara 34b) the halacha follows both Rabba and Rav Yosef, whichever way will be a stringency. In context of accepting Shabbat, Rama 261:1 rules like Rabba that Ben HaShemashot is 3/4 of a mil. | * '''Who do we follow, Rabba or Rav Yosef?''' The Rif (15a) writes that since it is unclear whether halacha follows Rav Yosef or Rabba, one should be strict to follow Rabba that Ben HaShemashot begins at Shekiyah. Then he says that it seems halacha should follow Rabba because halacha always follows Rabba with three exceptions and this isn't one of them. Similarly, Rambam (Shabbat 5:4) rules like Rabba that Ben HaShemashot begins at Shekiyah. Rabbenu Yonah (quoted by Rosh Shabbat 2:23) argues that since they're not arguing about which logic is correct but about what Rav Yehuda said (see Gemara 34b) the halacha follows both Rabba and Rav Yosef, whichever way will be a stringency. In context of accepting Shabbat, Rama 261:1 rules like Rabba that Ben HaShemashot is 3/4 of a mil. | ||
* | * '''Gemara Pesachim''' 94a records Rabbi Yochanan's statement that an average person can walk 30 mil from Netz HaChama until Shekiyah and 5 mil from Shekiyah until Tzet HaKochavim (according to Rashi D”H Ovav). The Gemara challenges this and explains really an average person can walk 32 mil from Netz HaChama until Shekiyah and only 4 mil from Shekiyah until Tzet HaKochavim. | ||
* '''The opinion of Rabbenu Tam:''' Tosfot (Pesachim 94a D”H Rabbi Yehuda and Shabbat 35a D"H Trei) is bothered how the Gemara Shabbat seems to say that from Shekiyah until Tzet HaKochavim a person can walk | * '''The opinion of Rabbenu Tam:''' Tosfot (Pesachim 94a D”H Rabbi Yehuda and Shabbat 35a D"H Trei) is bothered how the Gemara Shabbat seems to say that from Shekiyah until Tzet HaKochavim a person can walk 3/4 of a mil (according to the Rabba) and the Gemara Pesachim says a person can walk 4 mil. Rabbenu Tam answers that the Gemara Shabbat was referring to the end of the Shekiyah and from then until Tzet HaKochavim is 3/4 of a mil, while the Gemara Pesachim is discussing the end of Shekiyah which takes 4 mil until Tzet HaKochavim. Ramban (cited by Maggid Mishna), Maggid Mishna (Shabbat 5:4), and Ran (Shabbat 15a) agree. The Ran (Shabbat 15a) explains that according to Rabbenu Tam there's two Shekiyot. After the first it is still considered daytime until 3.25 mil after the beginning of the Shekiyah. Ben HaShemashot, which is uncertain day or night, spans .75 of a mil and begins from the beginning of the second Shekiyah. See Biur Halacha 261 D"H Metechila explains that the first Shekiyah is when the sun sets from our vision, and the second Shekiyah is when the light from the sun leaves the sky. | ||
* '''Does halacha follow Rabbenu Tam?''' The S"A 261:2 rules in accordance with Rabbenu Tam and states that from the beginning of the Shekiyah until Ben HaShemashot there's 3.25 mil and then Ben HaShemashot itself is .75 of a mil, which is equivalent to the time it takes to walk 1500 amot. | * '''Does halacha follow Rabbenu Tam?''' The S"A 261:2 rules in accordance with Rabbenu Tam and states that from the beginning of the Shekiyah until Ben HaShemashot there's 3.25 mil and then Ben HaShemashot itself is .75 of a mil, which is equivalent to the time it takes to walk 1500 amot. | ||
* '''Explanation of Rabbi Yose's opinion:''' Shmuel (Shabbat 35a) says that Rav Yose’s concept of Ben HaShemashot takes place after the Ben HaShemashot already finished. Tosfot (Shabbat 34b D"H Rabbi Yose) explains that even according to Rabbi Yose there’s a window of time when there is an uncertainty whether it is day or night but it isn’t as long as it is for Rabbi Yehuda. Rosh 2:23 discusses whether Rabbi Yose's Ben HaShemashot begins immediately after Rabbi Yehuda's or a while afterwards and doesn't come to a clear conclusion. | * '''Explanation of Rabbi Yose's opinion:''' Shmuel (Shabbat 35a) says that Rav Yose’s concept of Ben HaShemashot takes place after the Ben HaShemashot already finished. Tosfot (Shabbat 34b D"H Rabbi Yose) explains that even according to Rabbi Yose there’s a window of time when there is an uncertainty whether it is day or night but it isn’t as long as it is for Rabbi Yehuda. Rosh 2:23 discusses whether Rabbi Yose's Ben HaShemashot begins immediately after Rabbi Yehuda's or a while afterwards and doesn't come to a clear conclusion. | ||
