Narrated Aisha, Ummul Mu'minin: The Messenger of Allah (ﷺ) used to count the days in Sha'ban in a manner he did not count any other month; then he fasted when he sighted the new moon of Ramadan; but if the weather was cloudy he counted thirty days and then fasted.

Narrated Hudhayfah: The Prophet (ﷺ) said: Do not fast (for Ramadan) before the coming of the month until you sight the moon or complete the number (of thirty days); then fast until you sight the moon or complete the number (of thirty days).

Narrated Abdullah ibn Abbas: The Prophet (ﷺ) said: Do not fast one day or two days just before Ramadan except in the case of a man who has been in the habit or observing a fast (on that day); and do not fast until you sight it (the moon). Then fast until you sight it. If a cloud appears on that day (i.e. 29th of Ramadan) then complete the number thirty (days) and then end the fasting: a month consists of twenty-nine days.

Narrated 'Imran bin Husain: The Messenger of Allah (ﷺ) asked a man: Did you fast the last day of Sha'ban ? He replied: No. He said: If you did not observe a fast, you must fast for a day. One of the two narrators said: For two days.

Narrated Mu'awiyah: AbulAzhar al-Mughirah ibn Farwah said: Mu'awiyah stood among the people at Dayr Mustahill lying at the gate of Hims. He said: O people, we sighted the moon on such-and-such day. We shall fast in advance. Anyone who likes to do so may do it. Malik ibn Hubayrah as-Saba'i stood up and asked: Mu'awiyah, did you hear the Messenger of Allah (ﷺ) say something (about this matter), or is this something on the basis of your opinion? He replied: I heard the Messenger of Allah (ﷺ) as saying: Fast the month (in the beginning) and in the last.

Sulaiman b. 'Abd al-Rahman al-Dimashqi said about this tradition that al-Walid said: I heard Abu 'Amr al-Auza'i say: The word sirrahu means beginning of the month.

Narrated Ahmad b. 'Abd al-Wahid: On the authority of Abu Mushir. He said: Sa'id, that is, Ibn 'Abd al-'Aziz said: The meaning of the word sirraha is "in the beginning of it (the month)"

Narrated Kuraib: That Umm al-Fadl, daughter of al-Harith, sent him to Mu'aqiyah in Syria. He said: I came to syria and performed her work. The moon of Ramadan appeared while I was in Syria. We sighted the moon on the night of Friday. When I came to Median towards the end of the month (of Ramadan), Ibn 'Abbas asked me about the moon. He said: When did you sight the moon ? I said: I sighted it on the night of Friday. He asked: Did you sight it yourself ? I said: Yes, and the people sighted it. They fasted and Mu'awiyah also fasted. He said: But we sighted it on the night of saturday. Since then we have been fasting until we complete thirty days or we sight it. Then I said: Are the sighting of the moon by Mu'awiyah and his fasts not sufficient for us? He replied: No. The Messenger of Allah (ﷺ) commanded us to do so.

Al-Hasan said about a person who was in a certain city. He fasted on Monday, and twp persons bore witness that they had sighted the moon on the night of sunday. He said: That man and the people of his city should not fast as an atonement except that they know (for certain) that the people of a certain city of Muslims had fasted on Sunday. In that case they should keep fast as an atonement.

Narrated Ammar: AbuIshaq reported on the authority of Silah: We were with Ammar on the day when the appearance of the moon was doubtful. (The meat of) goat was brought to him. Some people kept aloof from (eating) it. Ammar said: He who keeps fast on this day disobeys AbulQasim (i.e. the Prophet) (ﷺ).

Narrated Abu Hurairah: The Messenger of Allah (ﷺ) as saying: Do not fast one day or two days just before Ramadan, except in the case of a man who has been in the habit of observing the particular fast, for he may fast on that day.

Narrated Umm Salamah, Ummul Mu'minin: She never saw the Prophet (ﷺ) fasting the whole month except Sha'ban which he combined with Ramadan.

Narrated AbuHurayrah: AbdulAziz ibn Muhammad said: Abbad ibn Kathir came to Medina and went to the assembly of al-Ala'. He caught hold of his hand and made him stand and said: O Allah, he narrates a tradition from his father on the authority of AbuHurayrah who reported the Messenger of Allah (ﷺ) as saying: When the middle of Sha'ban comes, do not fast. Al-Ala' said: O Allah, my father narrated this tradition on the authority of AbuHurayrah from the Prophet (ﷺ)

Narrated Abdullah ibn Umar: Husayn ibn al-Harith al-Jadli from the tribe of Jadilah Qays said: The governor of Mecca delivered a speech and said: The Messenger of Allah (ﷺ) took a pledge from us that we should perform the rites of hajj after sighting the moon. If we do not sight it and two reliable persons bear witness, we should perform the rites of hajj on the basis of their witness. I then asked al-Husayn ibn al-Harith: Who was the governor of Mecca? He replied: I do not know. He then met me later on and told me: He was al-Harith ibn Hatib, brother of Muhammad ibn Hatib. The governor then said: There is among you a man who is more acquainted with Allah and His Apostle than I. He witnessed this from the Messenger of Allah (ﷺ). He then pointed with his hand to a man. Al-Husayn said: I asked an old man beside me: Who is that man to whom the governor has alluded? He said: "This is Abdullah ibn Umar, and he spoke the truth. He was more acquainted with Allah than he. He (Abdullah ibn Umar) said: For this is what the Messenger of Allah (ﷺ) commanded us (to do).

Narrated Rib'i b. Hirash: On the authority of a man from the Companions of the Prophet (ﷺ): People differed among themselves on the last day of Ramadan (about the appearance of the moon of Shawwal). Then two bedouins came and witnessed before the Prophet (ﷺ) swearing by Allah that they had sighted moon the previous evening. So the Messenger of Allah (ﷺ) commanded the people to break the fast. The narrator Khalaf has added in his version: "and that they should proceed to the place of prayer (for 'Id)".

Narrated Abdullah ibn Abbas: A bedouin came to the Prophet (ﷺ) and said: I have sighted the moon. Al-Hasan added in his version: that is, of Ramadan. He asked: Do you testify that there is no god but Allah? He replied: Yes. He again asked: Do you testify that Muhammad is the Messenger of Allah? He replied: Yes. and he testified that he had sighted the moon. He said: Bilal, announce to the people that they must fast tomorrow.

Narrated Ikrimah: Once the people doubted the appearance of the moon of Ramadan, and intended neither to offer the tarawih prayer nor to keep fast. A bedouin came from al-Harrah and testified that he had sighted the moon. He was brought to the Prophet (ﷺ). He asked: Do you testify that there is no god but Allah, and that I am the Messenger of Allah? He said: Yes; and he testified that he had sighted the moon. He commanded Bilal who announced to the people to offer the tarawih prayer and to keep fast.

Narrated Abdullah ibn Umar: The people looked for the moon, so I informed the Messenger of Allah (ﷺ) that I had sighted it. He fasted and commanded the people to fast.

Narrated 'Amr b. al-'As: The Messenger of Allah (ﷺ) as saying: The difference between our fasting and that of the people of the Book is eating shortly before dawn.

Narrated Al-Irbad ibn Sariyyah: The Messenger of Allah (ﷺ) invited me to a meal shortly before dawn in Ramadan saying: Come to the blessed morning meal.