Begin Fasting Upon Sighting the Moon
Fasting should be started after sighting the moon of the month of Ramadan. If the moon cannot be sighted due to the murky sky then thirty days of Sha’ban should be completed. Similarly, complete the thirty days of Ramadan if the moon cannot be sighted at the end of Ramadan due to the murky sky.
‘Abdullah ibn ‘Umar radhiAllahu ‘anhu narrated that the Prophet salAllahu ‘alayhi wa sallam said, “Do not fast till you have sighted it (the new moon) and do not break it till you have sighted it, except when the sky is cloudy for you, and if it is so, then calculate it.” [Bukhari, Muslim]
Abu Huraira radhiAllahu ‘anhu narrated that the Prophet salAllahu ‘alayhi wa sallam said, “Fast when you see it and break the fast when you see it, and if it is too cloudy then complete the number (of days) of Sha’ban as thirty.” [Bukhari]
Fasting can begin upon the Testimony of a Muslim
‘Abdullah ibn ‘Umar radhiAllahu ‘anhu narrated that the people looked for the moon, so I informed the Messenger of Allah salAllahu ‘alayhi wa sallam that I had sighted it. He fasted and commanded the people to fast.
This indicates that it is not a requirement that a committee of men should sit and sight the moon. If a trustworthy Muslim testifies his sighting the moon, then his testimony will be accepted.
Do not Doubt the Beginning of Ramadan due to the Size of the Moon
Abu al-Bukhtari radhiAllahu ‘anhu said that we left Madina for minor pilgrimage. When we reached Nakhlah all of us saw the moon. Some people said this seems like the moon of the third night. Others said this seems like the moon of the second night. When we met ‘Abdullah ibn ‘Abbas radhiAllahu ‘anhu we said that we saw the moon. Some people called it the moon of the third night and some said it is of the second night. ‘Abdullah ibn ‘Abbas asked when we saw the moon. We replied on a such-and-such night. He replied the Prophet salAllahu ‘alayhi wa sallam has said that Allah subhanahu wa ta’ala makes it bigger for your sighting, therefore, it is of the night that you saw it on. [Muslim]
Therefore, do not argue over the size of the moon.
Du’a to be recited upon sighting the Moon
Talhah ibn ‘Ubaidullah radhiAllahu ‘anhu narrated that when the Prophet salAllahu ‘alayhi wa sallam sighted the moon he would recite the following du’a:
Begin Fasting and End Fasting by the Moon Sighting in the Present Country of Your Residence/Stay
It was proven from Ibn ‘Abbas radhiAllahu ‘anhu that when Kurayb told him that the people of Syria had started fasting on a Friday, Ibn ‘Abbas radhiAllahu ‘anhu said: We saw it on Saturday, and we will carry on fasting until we see the new moon or we complete thirty days. He did not follow the sighting of the people of Syria because Syria is far away from Madina and there may be a difference in moon sighting between the two.
Traveling from One Country to Another during Ramadan
If the number of fasts is greater than the fasts of the present country of stay then fasting for the additional days might either be abandoned or kept as voluntary fasts. If the count is less than the remaining fasts should be made up after ‘Eid.
Unable to Sight the Moon of Shawwal due to Murkiness
If one is unable to see the moon of Shawwal due to the murkiness and it is learned after fasting that the moon has been sighted then the fast should be broken.