BIRKAS ASHER NASAN LA'SECHVI VINAH [Birkas ha'Shachar: Asher Nasan la'Sechvi Vinah]
(Mishnah 1): Ben Gever was appointed over locking the gates.
(Rav): Keri'as ha'Gever (in the Mishnah Yoma 20a) is when a man announced.
(Beis R. Shila): It is when the rooster crowed.
Rav: A Mishnah says that Ben Gever was appointed...
You cannot say that this was a rooster's son! (Likewise, Keri'as ha'Gever refers to a man.)
Berachos 60b: When one hears a rooster, he says "Baruch Asher Nasan la'Sechvi Vinah Lehavchin Bein Yom u'Vein Laylah."
Rambam (Hilchos Tefilah 7:7): When one hears the rooster, he blesses ha'Nosen la'Sechvi Vinah. Any Berachah of these (Birkas ha'Shachar) that he is not obligated in, he does not bless it.
Hagahos Maimoniyos (7): Tosfos explains that one blesses even if he did not hear a rooster. "When one hears..." excludes in the Midbar, where there are no roosters, even of others. Alternatively, it excludes a deaf person. Similarly, a blind person does not bless Poke'ach Ivrim, since this is lacking from his body. The words of the Gemara are like the Rambam.
Magen Avraham (46:14): The Poskim hold that even if one was in the Midbar, or he is deaf or blind, he blesses all Birkas ha'Shachar. This requires investigation. I say that a blind person does not bless Poke'ach Ivrim, but a deaf person blesses ha'Nosen la'Sechvi Vinah. See Sof Siman 69. (A blind person can bless Yotzer ha'Me'oros. The Tur says that he benefits through them, for they enable others to guide him.) Emek ha'Berachah says that he should bring himself to be obligated, through hearing a rooster.
Rosh (Berachos 9:23): When one hears the rooster, he says Baruch she'Nasan la'Sechvi Vinah... The heart is called Sechvi - "Mi Nasan la'Sechvi Vinah." The heart understands. Through Binah, one distinguishes between day and night. Because also the rooster understands, and in Arabic rooster is called Sechvi, they enacted to say this Berachah when one hears a rooster. However, if he did not hear a rooster, he can bless, for the Berachah is merely praise to Hash-m who gave us understanding, and created all our needs. Even if one slept in a dark house, he can perceive the coming of day through a rooster's crowing.
Ran (Yoma 2a DH v'Havi): One may bless she'Asah Li Kol Tzarki on Yom Kipur [even though he may not wear shoes], for he blesses on the way the world runs, just like he may bless ha'Nosen la'Sechvi Vinah even though he did not hear a rooster.
Aruch (Erech Tarnegol): The Targum of la'Sechvi Vinah (Iyov 38:36) is l'Tarnegol Bara (a wild rooster) Bunsa. Tarnegol Bara is Duchifas (one of the Tamei species of birds). The Targum Yerushalmi/Yonason of b'Etziyon Gaver (Bamidbar 33:35, Devarim 2:8) is bi'Chrach Tarnegola. (Perush Yonason says that he expounds like "Kara Gever" (the rooster called).)
Pri Megadim (Igeres 5): See Ralbag on the verse Mi Nasan la'Sechvi Vinah. (He says that Sechvi refers to Hash-m's Hasghachah and Hashkafah (overseeing). The Targum of va'Yashkef is "va'Istachi", which is raw intellect.) Daytime represents the Midah of Emes. Morning is called Shachar. (One meaning of 'Shachar' is truth.) Night is called Erev, when everything is Me'urav (mixed, or confused). The Tarnegol Bara (Duchifas) is faithful about its oath and does not lie (Gitin 68b). In the morning, when a person rises and his Neshamah was above [in Shamayim] and remembers the oath of Har Sinai, we mention this.
Tashbatz (3:247): The Gemara says only "Baruch Nosen la'Sechvi Vinah." Bahag says only this. Sidur Rav Amram Gaon and the Rambam say "Lehavin Bein Yom u'Vein Laylah." They derived this from the verse, which says that Hash-m gave to the Sechvi Binah, or to the man who hears it, to know day and night. The Rif says "Lehavchin [Bein Yom...]", an expression of recognition and discernment between matters. The Isur of changing [the text of Berachos] is only changing whether or not the Berachah begins or ends with Baruch, or something primary to the Berachah, e.g. mention or request of dew or rain. We are not particular whether one says Lehavin or Lehavchin. One may add in the Berachah of Refu'ah or income if he has a need, and we add Piyutim into Berachos and Tefilah. This is not changing the text, if the Piyut pertains to the Berachah.
Shulchan Aruch (OC 46:1): When one hears a rooster, he blesses ha'Nosen la'Sechvi Vinah.
Levush (2): Letter of the law, one should bless every Berachah in its time. When one hears a rooster, even if he is still lying in his bed, he should bless ...ha'Nosen la'Sechvi Vinah Lehavchin Bein Yom u'Vein Laylah. Also the rooster knows to distinguish between day and night. It crows every day at the same time. One benefits from its crowing. It informs him that it is close to day, and it is time to rise. Therefore, a Berachah was enacted for this.
Levush (5): The Berachos Asher Yatzar, Elokai Neshamah and ha'Nosen la'Sechvi Vinah were enacted due to their formation. Therefore, we say them together. The other Berachos are due to benefit.
Birkei Yosef (2): Even though Rosh Hashanah 26a says that Sechvi is the rooster, in the simple meaning of the verse it is the heart. The Pri Chodosh was drawn after the Gemara there.
Ha'arah 1: In Chomas Anach (on Iyov), the Birkei Yosef defended the Pri Chodosh, since the Bavli and Yerushalmi and one text of the Targum on Iyov say so. The Ramban resolved the two explanations.
Aruch ha'Shulchan (3): One may not benefit from this world without a Berachah. Therefore, they enacted to bless ha'Nosen la'Sechvi Vinah. All Birkos ha'Shachar are about man's Hana'os. The primary Hana'ah is during the day, when it is light, and he does all his needs. Therefore, one must bless on this. The Gemara's text is "Asher Nasan [la'Sechvi Vinah]." The text in the Rambam, Tur and Shulchan Aruch is "ha'Nosen." This is primary. All Berachos are in the present, and not in the past, e.g. Yotzer ha'Me'oros, Nosen ha'Torah, Borei Peri ha'Adamah. This is because Hash-m constantly acts every moment, unlike a mortal who does a labor, and then it stands by itself, and he ceases to supervise it. Hash-m never ceases to supervise his works - "l'Oseh Orim Gedolim." (Asher Yatzar begins in the past, for one blesses on the past action [of creation], therefore we conclude in the present "Rofei Kol Basar.")
Kaf ha'Chayim (10): Some say that we bless because the rooster understands when is midnight and midday. Sha'ar ha'Kavanos (the Ari Zal) says that Sechvi is Gavriel, the secret of Gevurah. In the second half of the night, Gevyrah gets an influence of Binah. Even a deaf person blesses, and so says Ben Ish Chai.
Shulchan Aruch (8): If one was not obligated in one of these Berachos, e.g. he did not hear a rooster, he blesses without Hash-m's name.
Rema: Some say that even if one was not obligated, he blesses. The Berachah is not for himself. Rather, it is because Hash-m created needs of the world. This is the custom. One should not deviate.
Gra (DH Kol): The Beis Yosef says that since there is an argument about this (between the Rambam, and the Rosh and Ran) one blesses without Hash-m's name.
Mishnah Berurah (25): Chayei Adam says that a deaf person should not bless ha'Nosen la'Sechvi Vinah before dawn.
Kaf ha'Chayim (50): The Ari Zal says that all the Berachos are based on the way of the world, therefore we do not apply Safek Berachos Lehakel.
Shulchan Aruch (47:13): One who rises before dawn blesses all the Berachos, except for ha'Nosen la'Sechvi Vinah.
Magen Avraham (13): Kesavim [of the Ari Zal] and the Zohar permit saying it right after midnight. I say that this is only if he hears a rooster. In any case, it is good to be careful l'Chatchilah.
Eshel Avraham (13): I wrote in 46:14, that at midnight, one cannot bless on the way of the world, so one must hear a rooster. The Pri Chodosh agreed that one may bless at night, and he used to do so. See Sof ha'Siman. "... Va'Yanuchu (they camped) b'Avronah" (this world is Avar v'Gaz, i.e. passes and vanishes). The next encampment was b'Etziyon Gaver (its Targum is bi'Chrach Tarnegola). The Etzah (counsel) is to hear the rooster, which announces.
Sha'arei Teshuvah (13): The Zohar says that when the Gavra calls, one should bless. Shalmei Tzibur wrote that we may bless even if it did not call. The Zohar means that through the rooster, they knew that it is past midnight. The custom is to bless in the last part of the night.
Mishnah Berurah (30): Even if one rose early after midnight, and he intends to sleep again Shinas Keva, even so he may bless all of these Berachos and need not bless again in the morning.
Mishnah Berurah (31): The Acharonim concluded that also this Berachah one may say before dawn, but some say that this is l'Chatchilah only if he heard a rooster. B'Di'eved he was Yotzei even if he did not hear a rooster, but only if he blessed after midnight. Before midnight, even b'Di'eved he must bless again, even if he heard a rooster.
Bi'ur Halachah (DH Mevarech): The Be'er Heitev and Derech ha'Chayim are stringent l'Chatchilah even if he heard a rooster, but the Pri Chodosh and Gra themselves were lenient in practice. Also, the Pri Megadim connotes that one may bless before dawn even if he did not hear a rooster. Only after midnight (i.e. long before dawn) one must hear a rooster [in order to bless]. The Chayei Adam explains that the Magen Avraham said to see 46:8, i.e. the Rema there is lenient even if he did not hear a rooster at all, for the Gemara discusses the normal way of the world. If so, we can explain the Zohar "when the rooster crows..." similarly. In any case, it is good to be stringent l'Chatchilah, i.e. if he did not hear a rooster. If he heard, one may be lenient l'Chatchilah.
Kaf ha'Chayim (30, citing Machazik Berachah): Sefer ha'Pardes says that Rashi used to bless all the Berachos, including ha'Nosen la'Sechvi Vinah, before dawn. The Ari Zal holds like this.
Aruch ha'Shulchan (52:8): If one did not bless ha'Nosen la'Sechvi Vinah before Shemoneh Esre, he may not bless afterwards, for he already blessed Yotzer ha'Me'oros. One must be careful that this not occur.
Pischei Teshuvah (YD 341:17): Aninus does not apply on Yom Tov night. One may say all Birkas ha'Shachar from midnight, except for ha'Nosen la'Sechvi Vinah. Therefore, if he did not say them before, he says them after the burial, since he was already obligated in them, except for ha'Nosen la'Sechvi Vinah.