Related על ברכות 8:8

Just like the Torah established a set time to read the Shema, so too the Sages established a set time for [the] prayer [of Shemoneh Esreh]. Why did they say [that] the morning prayer [of Shmoneh Esreh can be prayed only] until noon? Because the morning Tamid (daily offering) [sacrifice] could be brought [only] until noon. Rebbi Yehudah says, “[The morning prayer of Shmoneh Esreh can be prayed only] until [the end of the first] four hours [of the day].” And why did they say that the Mincha (afternoon) prayer [of Shemoneh Esreh can only be prayed] until the evening? Because the afternoon Tamid [sacrifice] could be brought [only] until the evening. Rebbi Yehudah says, “[The Mincha prayer of Shmoneh Esreh can be prayed only] until Plag Hamincha.” And when is Plag Hamincha? Eleven minus one quarter hours [of the day] (i.e. 10 ¾ hours). And why did they say that the evening prayer [of Shmoneh Esreh] does not have a set time? Because the limbs and fats [of the sacrifices] could be brought the whole night. And why did they say that the Mussaf prayer [of Shmoneh Esreh can be prayed] the whole day? Because the Mussaf (additional offering) sacrifice could be brought the whole day. Rebbi Yehudah says, “[The Mussaf prayer can be prayed] until [the end of the first] seven hours [of the day].”

Everyone is obligated in [saying] Birkat Hamazon (Grace After Meals), Kohanim (Priests), Leviim (Levites), and Yisraelim (Israelites, regular Jews), converts [to Judaism], freed [non-Jewish] slaves, Chalalim (Kohanim who have lost their priestly status), Natinim, Mamzerim (bastards), [a person] castrated by [a deliberate act of another] person, [a person who was] born castrated, [a person] with [one or both] testicles crushed, and [a person] with a cutoff member. All of them are obligated [in saying Birkat Hamazon] and they can absolve others (i.e. say it for others) of their obligation [of saying Birkat Hamazon]. A Tumtum (a person of unknown sex), and a hermaphrodite are obligated [in saying Birkat Hamazon], but they cannot absolve others (i.e. say it for others) of their obligation [of saying Birkat Hamazon].

[If] a Non-Jew says a blessing [for anything] using God’s name we answer after him Amen [even if we did not hear the whole blessing]. [If] a Samaritan says a blessing [for anything] using God’s name we do not answer after him Amen until we hear the whole blessing.