The Messenger of Allah ﷺ used to pray Dhuhr when the sun had passed its zenith, pray Asr between these two prayers of yours, pray Maghrib when the sun had set, and pray Isha when the twilight had disappeared. Then he said, following that, "And he used to pray Fajr from when the eye could discern things clearly."
كان رسول الله ﷺ يصلي الظهر إذا زالت الشمس، ويصلي العصر بين صلاتيكم هاتين، ويصلي المغرب إذا غربت الشمس، ويصلي العشاء إذا غاب الشفق ثم قال: على إثره، ويصلي الصبح إلى أن ينفسح البصر.
Reported by Nasai (552). He said, Ismail bin Masud and Muhammad bin Abdul-Ala told us, they said, Khalid told us, from Shuba, from Abu Sadaqa, from Anas bin Malik, and he related the hadith. Its chain is sahih. Khalid is Ibn Harith bin Ubayd Hujaymi, one of the men found in the six major collections. Abu Sadaqa's name was Tawba Ansari, freedman of Anas, of Basra. A group narrated from him, including Nasai in "Kuna" as quoted by Hafiz in Tahdheeb, and Dhahabi said in Kashif that he was reliable. Moreover, he was one of Shuba's teachers, and it is well known that Shuba narrated only from reliable narrators. Shuba also praised him favorably in the narration of Imam Ahmad (12723), for Imam Ahmad reported it from Hajjaj (that is, Ibn Muhammad Masissi), who said, Shuba told me, from Abu Sadaqa, freedman of Anas, and Shuba praised him favorably, he said, I asked Anas about the prayer of the Messenger of Allah ﷺ, and he related the hadith, in which it states, "And the dawn prayer, when Fajr rises, until the sight can distinguish things clearly." Ahmad also narrated it (12311) from Muhammad bin Jafar, Shuba told us, from Abu Sadaqa, freedman of Anas, relating something similar.The conclusion is that Abu Sadaqa is reliable.The hadith has another route, reported by Abu Yaala (3991) Athari. He said, Ahmad bin Hatim told us, Mutamir bin Sulayman told us, he said, a man called Bayan told me, he said, I said to Anas, tell me about the time of the Messenger of Allah's ﷺ prayers. He said, He used to pray Dhuhr when the sun began to decline, and he used to pray Asr between your first prayer and Asr, and he used to pray Maghrib when the sun set, and he used to pray Isha when twilight vanished, and he used to pray the dawn prayer when Fajr rose, when sight could just begin to distinguish things. All that lies between these times is a valid time, or he said, a prayer.Bayan is Ibn Bishr Ahmasi, Abu Bishr Kufi, one of the men found in the six major collections. Haythami cited this route in Majma (1/304) and said, its chain is hasan. Busiri also cited it in Ithaf Khayra (2/46), along with another route from Ahmad bin Raja, from Mutamir bin Sulayman, with the same wording, and said, this hadith's narrators are reliable.His statement, "he used to pray Asr between your first prayer," meaning Dhuhr, and Asr here refers to the final part of the daytime. And his statement, "he used to pray the dawn prayer when Fajr rose, when sight could just begin to distinguish things," in another narration, "when sight could see clearly," meaning that sight begins to perceive things at a distance, that is, referring to the brightening of dawn.The meaning of the hadith, when considered alongside the previous hadiths, is that the Fajr prayer begins in the darkness before dawn and its time extends into the brightening of dawn, as will be explained in the hadith of Rafi bin Khadij.As for what has been reported from Abu Hurairah as a statement of the Prophet, "Indeed prayer has a beginning and an end. The beginning of Dhuhr's time is when the sun passes its zenith, and its end is when Asr's time begins. The beginning of Asr's time is when its time begins, and its end is when the sun turns yellow. The beginning of Maghrib's time is when the sun sets, and its end is when twilight disappears. The beginning of the later Isha's time is when twilight disappears, and its end is when the night reaches its middle. The beginning of Fajr's time is when Fajr rises, and its end is when the sun rises," this is daif.It was reported by Tirmidhi (151), who said, Hannad told us, Muhammad bin Fudayl told us, from Amash, from Abu Salih, from Abu Hurairah, and he related the hadith. Tirmidhi said, I heard Muhammad (Bukhari) say, "The hadith of Amash from Mujahid concerning the prayer times is more sahih than the hadith of Muhammad bin Fudayl from Amash, and the hadith of Muhammad bin Fudayl is mistaken, Muhammad bin Fudayl erred in it." End of quote.Tirmidhi then reported from Hannad, Abu Usama told us, from Abu Ishaq Fazari, from Amash, from Mujahid, who said, it used to be said, "Indeed prayer has a beginning and an end," and he related something similar in meaning to the hadith of Muhammad bin Fudayl from Amash. End of quote.What Bukhari said was also said by more than one scholar of hadith, among them Abu Hatim, as his son quoted from him in Ilal (1/101), "This is a mistake. Ibn Fudayl erred in it. The companions of Amash narrate it from Amash, from Mujahid, as his own statement." Among them also is Daraqutni, for after reporting the hadith in his Sunan (1/262) from the narration of Ibn Fudayl, he said, "This is not sound as a connected hadith. Ibn Fudayl erred in its chain. Others narrate it from Amash, from Mujahid, as a disconnected report." He then presented it through the route of Zaida bin Qudama, from Amash, from Mujahid, and said, "This is more sahih than the version of Ibn Fudayl, and Abthar bin Qasim corroborated Zaida." End of quote.Among them also is Bayhaqi, who reported it in his Sunan (1/376) through the route of Zaida, from Amash, from Mujahid, as a disconnected report, and after reporting the aforementioned hadith through the route of Muhammad bin Fudayl, said, "Abbas bin Muhammad Duri says, I heard Yahya bin Main weaken the hadith of Muhammad bin Fudayl, from Amash, from Abu Salih, from Abu Hurairah." Bayhaqi said, "I think Yahya means the statement, 'Indeed prayer has a beginning and an end.'" End of quote.These critical assessments are based on a careful examination of Amash's narrations, which is a well-known method among the scholars of hadith, one they employed for scrutiny and refinement.As for Ibn Jawzi's statement, "Ibn Fudayl is reliable, and it is possible that Amash heard it from Mujahid as a disconnected report, and also heard it from Abu Salih as a connected report," and likewise Ibn Qattan's statement, "It is not unlikely that Amash had two routes for this, one disconnected and the other connected as a statement of the Prophet, and the one who reported it as connected is a truthful scholar, whom Ibn Main deemed reliable, namely Muhammad bin Fudayl" in Nasb Raya (1/231), this is merely a possibility, and it is not sufficient to refute those who carefully examined the narrations and judged them to be mistaken.