Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) says: One day I became aroused and kissed my wife while I was fasting, and I came to the Prophet (peace and blessings be upon him). I said: "Today I have done a very grave thing: I kissed while fasting." The Messenger of Allah (peace and blessings be upon him) said: "What do you think if you rinsed your mouth with water while fasting?" He says: I said: "There is no harm in that." The Messenger of Allah (peace and blessings be upon him) said: "Then what is troubling you?"
Imam al-Shafi'i (may Allah have mercy on him) says: If he swallowed it after dawn, he makes up a day in its place.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8018
It is narrated from Sayyiduna Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "When one of you hears the call (to prayer) while the vessel is in his hand, let him not put it down until he has fulfilled his need from it."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8019
Sayyiduna Abu Hurayrah (may Allah be pleased with him) says: The muezzin would call the adhan when dawn broke, and the Messenger of Allah (peace and blessings be upon him) said: "When one of you hears the call while the vessel is in his hand, let him fulfil his need."
If this is authentic, the generality of the people of knowledge understand it to mean that he (peace and blessings be upon him) knew that the caller was calling before dawn broke, so that his drinking would take place just before dawn. The narrator's words "the muezzins used to call the adhan when dawn broke" may be a disconnected report from someone below Abu Hurayrah, or a report about the second adhan, while the Prophet's (peace and blessings be upon him) words "When one of you hears the call while the vessel is in his hand" refer to the first call, so that it agrees with the other reports.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8020
It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that he (peace and blessings be upon him) said: "Let not the adhan of Bilal prevent any of you from his sahur, for he only calls to wake up those of you who are sleeping and to send back those of you who are standing (in prayer)."
Jarir says that he did not indicate the dawn by pointing lengthwise, but pointed widthwise, because it is not lengthwise.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8021
Sayyiduna Ibn Umar and Sayyidah Aishah (may Allah be pleased with them) say that the Messenger of Allah (peace and blessings be upon him) said: "Bilal calls the adhan while it is still night, so eat and drink until you hear the adhan of Ibn Umm Maktum."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8022
Sayyiduna Shayban (may Allah be pleased with him) says: I entered the mosque, called the adhan and sat aside in a corner. The Messenger of Allah (peace and blessings be upon him) said to me: "O Abu Yahya!" I said: "Yes." He (peace and blessings be upon him) said: "Come closer and eat." I said: "I intend to fast." He (peace and blessings be upon him) said: "I too intend to fast, but our muezzin has something wrong with his eyesight, or something else, and he called the adhan before dawn broke."
Ash'ath bin Sawwar is alone in narrating this hadith. If it is authentic, it seems that the adhan of Sayyiduna Ibn Umm Maktum (may Allah be pleased with him) took place before dawn, so the Messenger of Allah (peace and blessings be upon him) did not refrain from eating. On the basis of what we have mentioned, the reports agree and do not differ; and success is from Allah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصيام / 8023