Question (R. Yitzchak bar Avodimi): What is the source that blood becomes Pasul at Shki'as ha'Chamah?

Answer: "B'Yom Hakrivo Es Zivcho Ye'achel" - you may offer (the blood) only on the same day of the Shechitah.

Berachos 26b (Beraisa): One may pray Minchah until Erev (evening), the latest time for the afternoon Tamid;

R. Yehudah permits (only) until Plag ha'Minchah, the latest time for the afternoon Tamid.

(Beraisa - R. Yehudah): One may pray until Plag ha'Minchah, i.e. 10 and three quarters hours.

27a (Rav Chisda): Rav used to pray Ma'ariv of Shabbos on Erev Shabbos before dark. This shows that the Halachah follows R. Yehudah! (According to Chachamim, it is still the time for Minchah, so one may not pray Ma'ariv then!)

Objection: Rav Huna and Rabanan used to wait until dark to pray Ma'ariv. This shows that the Halachah follows Chachamim!

Conclusion: Since the Halachah was not fixed like either opinion, one may follow either one.

Rif and Rosh (Berachos 18b and 4:3): The Halachah was not fixed like either opinion regarding Minchah, so one may follow either one.

R. Yonah: Do not say that 'until Erev' means until Tzeis ha'Kochavim, which is truly night. Here, Erev means Shki'as ha'Chamah. We say in Zevachim that that blood is disqualified at Shki'as ha'Chamah (sunset). I.e. from Shki'ah and onwards is not the time for Zerikah of the afternoon Tamid. Tefilas Minchah corresponds to the afternoon Tamid. The primary (Avodah) of the Tamid is Zerikah! Just like Zerikah is only until Shki'ah, also Minchah.

Rambam (Hilchos Tefilah 3:4): The time for Minchah Ketanah is from nine and a half hours until an hour and a quarter remain in the day. One may pray until Shki'as ha'Chamah.

Hagahos Maimoniyos (3): R. Chananel says that nowadays all of Yisrael follow Rabanan to pray Minchah until Erev, and R. Yosi in the Yerushalmi, that Minchah is not equated to the afternoon Tamid, rather, to the Ketores - "Tikon Tefilasi Ketores Lefanecha." Rebbi (Eliezer) said that a Tefilah that is Keva is not supplication. Some say that this is one who does not pray Im Dimdumei Chamah (when the sun is setting). R. Yochanan said that it is a Mitzvah to pray then - "Yira'ucha Im Shemesh (v'Lifnei Yare'ach)." Even though in Eretz Yisrael they cursed (those who rule like this) (Berachos 29b), this is only if one delays more than this. Slightly before sunset is fine. The Yerushalmi says that R. Yosi used to pray Im Dimdumei Chamah - "Al Zos Yispalel Kol Chasid Elecha l'Es Metzo", i.e. l'Es Metzo of the day (when it ends). Even though the time for Minchah is from six and a half hours until the end of the day, it is better from Minchah Ketanah and onwards, as long as he does not delay too long. R. Tam says that we hold like Rav, who prayed (Ma'ariv) of Shabbos on Erev Shabbos, and the same applies to during the week.

Kesef Mishneh: The Rambam says 'until an hour and a quarter remain in the day', i.e. until Erev, like Chachamim, who say that Minchah is until Erev. Why didn't he say 'until Shki'ah'? Rather, it seems that he holds like the Rosh said in the name of a Gaon, that one who prays Ma'ariv (after Plag ha'Minchah) may pray Minchah only until Plag ha'Minchah, for one may not do sometimes like Chachamim and sometimes like R. Yehudah. The Rambam allows until one and a quarter hours remain, like R. Yehudah. He concludes that if one wants to hold like the first Tana, he may pray until Shki'as ha'Chamah.

Hagahos Maimoniyos (8): Avi ha'Ezri says that one who wants to follow Chachamim may pray Minchah until Erev, i.e. until Shki'as ha'Chamah, which is Tzeis ha'Kochavim. He may not pray Ma'ariv or read Kri'as Shema until after Tzeis ha'Kochavim. One cannot pray Minchah and Ma'ariv between Plag ha'Minchah and Tzeis ha'Kochavim. Regarding Minchah this is like the Ge'onim, who rule like Chachamim, and regarding Ma'ariv it is like R. Tam, who rules like R. Yehudah. One who does like R. Tam is not Yotzei Kri'as Shema according to the Ge'onim. One who does like the Ge'onim is Yotzei (everything) according to R. Tam, for he agrees that one may follow either opinion. In any case, our custom is like R. Tam. Avi ha'Ezri says that it is haughtiness to be stringent like the Ge'onim, for this is not our custom, unless he is a Parush and is meticulous also about other Mitzvos.

Rosh (ibid.): A Gaon wrote that one who prays Ma'ariv early may pray Minchah only until Plag ha'Minchah, like R. Yehudah. The Halachah follows R. Yehudah or Chachamim, but not both of them! Therefore, if one prays Minchah (after Plag ha'Minchah) until evening, he may not pray Ma'ariv after Plag ha'Minchah (before dark), for one cannot do once like R. Yehudah and once like Chachamim.

R. Yonah (18b DH d'Avad): One should not act in a way that contradicts himself. Since our custom is to pray Minchah after Plag ha'Minchah like Chachamim, we may not pray Ma'ariv before Shki'ah like R. Yehudah. Rather, we must do totally like Chachamim. However, b'Di'eved if one prayed after Plag ha'Minchah with intent to to be Yotzei Ma'ariv, he was Yotzei. We do not obligate him to pray again.

Rosh (1:1): We sometimes pray Minchah after Plag ha'Minchah, like Chachamim. Regarding Kri'as Shema, we consider this time to be night, like R. Yehudah. These are contradictory leniencies! The Gemara says that one may follow either one, i.e. one may always do like R. Yehudah, or always like Rabanan. One may not adopt the leniencies of both! We can say that regarding Tefilah, they were lenient. R. Tam says that Minchah is until Plag ha'Minchah, for the Tamid was offered until then, but regarding Kri'as Shema (one is Yotzei only at night) for people do not lie down then (from Plag ha'Minchah, until night). I disagree. To justify our custom is, we can say that we rely on other Tana'im who say that the time for Kri'as Shema is before Tzeis ha'Kochavim. We are lenient about Tefilah. Also, it is pressed circumstances. The Tzibur gathers for Minchah, and if they would not say Shema and pray until Tzeis ha'Kochavim, everyone would go home, and it would be an exertion to gather again later, and they would not pray with a Tzibur. Rav Hai Gaon says that if the Tzibur prays Ma'ariv before Tzeis ha'Kochavim, one should pray with the Tzibur, and say Kri'as Shema afterwards. However, one who does so must be careful not to pray Minchah after Plag ha'Minchah, since he considers this time night regarding Ma'ariv.

Tosfos (56a DH Minayin): For all other laws of the Torah, the day ends later, at Tzeis ha'Kochavim. Zerikah is different. It seems that Rashi holds that also here, Shki'as ha'Chamah refers to the end of Shki'ah, i.e. Tzeis ha'Kochavim.

Mordechai (Shabbos 455): Blood is disqualified at the beginning of Shki'ah, at least mid'Rabanan.

Shulchan Aruch (OC 233:1): The time for Minchah is until night according to Rabanan, and according to R. Yehudah it is until Plag ha'Minchah, i.e. 10 and three quarters hours.

Mishnah Berurah (2): The Shulchan Aruch permits until night. Really, it is until about a quarter hour earlier, for this is Bein ha'Shemashos, and all agree that one may not pray Minchah then.

Kaf ha'Chayim (4): Shiltei ha'Giborim said that Minchah is only until Shki'ah. Sha'agas Aryeh says that it is until Tzeis ha'Kochavim, and the Rema explicitly says so below.

Kaf ha'Chayim (5): The custom in Yerushalayim is not to pray Minchah from when the crow cries, which is 11 minutes after Shki'ah.

Rema: We calculate these hours based on 12 hours in the day, even if it is a long day.

Mishnah Berurah (4): Some say that the 12 hours are from dawn until Tzeis ha'Kochavim. If so, R. Yehudah permits until one and a quarter hours before Tzeis ha'Kochavim, and Chachamim permit until Tzeis ha'Kochavim. The Shulchan Aruch holds like this. Some say that the 12 hours are from sunrise until sunset. If so, R. Yehudah permits until one and a quarter hours before sunset, and Chachamim permit until sunset.

Shulchan Aruch (ibid.): We concluded that one may follow either opinion. One must consistently follow one opinion. If he follows Rabanan and prays Minchah until night, he may not pray Ma'ariv after Plag ha'Minchah. If he follows R. Yehudah and prays Ma'ariv from Plag ha'Minchah, he must be careful not to pray Minchah at that time. Nowadays the custom is to pray Minchah until night, so one may not pray Ma'ariv before Shki'ah. B'Di'eved, if one prayed Ma'ariv after Plag ha'Minchah, he was Yotzei. In pressed circumstances, one may pray Ma'ariv after Plag ha'Minchah.

Beis Yosef (DH u'Mah she'Chosav v'Hu): Also Ohel Mo'ed says in the name of Rav Hai Gaon that one must consistently follow one opinion. He cites Ba'al ha'Hashlamah to say that nowadays, due to pressed circumstances the practice is to sometimes follow R. Yehudah and sometimes Rabanan. This is acceptable. It is no worse than one who rises early to travel. He may recite (Shema) earlier than the normal time. R. Yonah is stringent. Nowadays, people are lenient. Even though they pray Ma'ariv after Plag ha'Minchah, they do not refrain from praying Ma'ariv in the same time period, even though the leniencies contradict each other. They rely on what the Rosh wrote (1:1) according to R. Tam. Also the Rashba says that we are lenient about Tefilah. The Rosh rejected R. Tam, and he concluded that if one does like Rav Hai Gaon and prays Ma'ariv with a Tzibur before Tzeis ha'Kochavim, he may not pray Minchah after Plag ha'Minchah, since he considers this night regarding Ma'ariv. Even so, people rely on R. Tam.

Mishnah Berurah (9): When the Mechaber says 'Shki'ah', he means the end of Shki'ah, i.e. shortly before Tzeis ha'Kochavim. Really, he should not pray until Tzeis ha'Kochavim, for before then is Safek night. The Mechaber was not particular to be precise, for it is a small difference.

Kaf ha'Chayim (9): A woman need not be concerned about contradictory leniencies. Since she is busy with needs of the house, it is like pressed circumstances for her.

Kaf ha'Chayim (10): Olas Tamid says that a Chasid should pray Minchah before Plag ha'Minchah, and Ma'ariv after Tzeis ha'Kochavim, to fulfill both opinions. I say that the best time for Minchah is after Plag ha'Minchah.

Rema: In these lands we pray Ma'ariv from Plag ha'Minchah, so one may not pray Minchah afterwards. B'Di'eved, or in pressed circumstances, one was Yotzei if he prayed Minchah until night, i.e. until Tzeis ha'Kochavim.

Darchei Moshe ha'Aruch (1): In pressed circumstances, Maharil used to pray Minchah close to Tzeis ha'Kochavim. He said that even though it appears to be night in the city, it is still day, like R. Yosi said (Shabbos 118b) 'may my portion be among those who bring in Shabbos early in Tiverya.' This is only in a city in which the houses are tall, or it is in a valley. (It gets dark early, and people accept Shabbos then. This is Midas Chasidus, for really, it is still day - PF.) Nowadays, the custom is to pray Minchah and Ma'ariv next to each other. We hold like Chachamim; we pray Ma'ariv before night due to the difficulty of gathering people a second time. The Tur (Siman 235) says so. If an individual did not pray Ma'ariv with the Tzibur, he should wait until night.

Gra (DH v'Im): Even though the Rosh disagreed with R. Tam, b'Di'eved or in pressed circumstances one may rely on R. Tam. All agree that Minchah ends at the first time for Ma'ariv.

Mishnah Berurah (11): In pressed circumstances, one who normally prays Minchah after Plag ha'Minchah may be lenient to pray Ma'ariv at this time, but only if today he prayed Minchah beforehand. If not, he contradicts himself regarding this very day! This is for an individual. If a Tzibur prayed Minchah, and if they would go home it would be hard to gather them again, and Tefilah b'Tzibur would be totally Batel, Acharonim were lenient to permit Ma'ariv close to Minchah.

Mishnah Berurah (14): Even though the Shulchan Aruch and Rema connote that that we, who pray Ma'ariv after Tzeis ha'Kochavim, may pray Minchah until Tzeis ha'Kochavim, many Poskim say that Minchah is only until Shki'ah. Therefore, everyone must be careful to finish his Tefilah before the sun leaves our view. It is better to pray Minchah alone in the time than afterwards with a Tzibur. B'Di'eved, one may rely on the lenient opinions to pray after Shki'ah until a quarter hour before Tzeis ha'Kochavim. One must pray as soon as possible to avoid a Safek Bein ha'Shemashos. If stars can be seen, surely the time already passed. In Eretz Yisrael they cursed one who prays Im Dimdumei Chamah, lest he not pray in time.

Kaf ha'Chayim (12): The Ari Zal would pray Minchah close to sunset, and Ma'ariv shortly after, so that all three Tefilos are during the day. He relied on R. Tam.

Bi'ur Halachah (DH d'Hainu): B'Di'eved, if one prays after Shki'ah, he should stipulate that if it is still day, this is Minchah, and what he prays after Tzeis ha'Kochavim is Ma'ariv. If it is already night, this is Ma'ariv, and what he prays later is Tashlmumin (compensation) for Minchah.