The Book of Lights and Watchtowers: On Determining the Months

Book 7, Chapter 1

Which Relates How People Are Divided Regarding the Beginnings of Months and What Each Group Says

The nation is divided into three groups with regard to knowing the beginnings of months. One group said that the crescent [moon] is the cause of the month and its sign, and that beginnings of months are known by it and by nothing else. The second group rejected this and did not at all make the [crescent] moon the cause for beginning a month and [a way of] knowing it. The third group obligated making [the moon the reason for beginning a month] in some but not in all months and arranged the following [months] in a sequence [of twenty-nine- and thirty-day months].

Those who make the moon the cause of the month are divided into four groups. One group says that [the beginning of a month] can be known by sighting the crescent in the west at the end of the day after sunset. And [the sighting] must be after it disappears in the west. If [the crescent] is sighted, the time at which it is sighted is the first day of the month. They seek it when twenty-nine [days] have passed since its [previous] sighting. If they see it, [they declare a new month]. Otherwise, they assume that the month is thirty days long, and the thirty-first day is the beginning of the next month. This is the approach of ‘Anan, of most early Karaites and of all Karaites of this time. It is said that Boethus—whom we mentioned in the beginning of this book and said that he and Tsadok were students of Antigonus—said the same thing. This was also the approach of early Rabbanites, the followers of the Mishnah, and it is recorded therein. We will explain this later.

The second group are supporters of [determining the beginning of the month with reference to] conjunction and separation. They say that if the moon enters conjunction with the sun and then separates from it, this is the sign of the beginning of the month. People say that the Rabbanites had shifted from sighting the crescent to this [method] before they innovated this calendar that they follow now. This is also the approach of Isma‘īl al-‘Ukbarī [ninth century] and [Abū ‘Imrān] Mūsā [al-Za‘afrānī] al-Tiflīsī [early ninth century]. Daniel al-Qūmisī [ninth century] had taken this approach before he started to support the [method of] sighting, and so did all early Karaites of Baṣra and the Khorāsānians. They call it [i.e., the conjunction] the molad, meaning that when the moon separates from the sun, it [i.e., the moon] is born. They say two [different] things about it. Some of them maintain that if the separation occurs between the beginning of the day and 641 parts after the sixth hour, which is midday, this day is the beginning of the month. But if it occurs after it, by one part or more, the beginning of the month is on the next day because the [time for a new month] sacrifice had already passed. Others say that whatever time of day it happens, this day itself is the beginning of the month, even if only one part remains of that day. This is because it is not permissible that the cause of renewing the month has taken place, but the day on which it takes place belongs to the old month. This is the approach of Isma‘īl al-‘Ukbarī and of al-Tiflīsī. According to them, the month is 29 days, 12 hours, and 793 parts long. At the end of this count the month ends and another month begins. They say that this is also the approach of the Samaritans and that they maintain that they have transmitted it.

The third group among those who said that the moon is the sign of the month by which [its beginning] can be known are supporters of the full moon. They are the Maghārians whom we mentioned above in the beginning of the book. They maintain that when the moon becomes full, that day is the beginning of the month.

The fourth group, as related on the authority of some people, are those who maintain that when the moon disappears in the east, that day is the beginning of the month.

The second [major] group, which does not make the moon the reason for [beginning] a month, are divided in their approach into two. The first [approach is that of] the Sadducees. They maintain that all months are thirty days long and that this does not change. The second one is the calendar based on lo badu Pesaḥ¹ to which the Rabbanites shifted and which the community follows until now.

The third major group are those who make the moon the cause of the month, in some months but not in others. They are also in two groups. The first one is Benjamin al-Nahāwandī. He maintains that months always follow the sequence of thirty and twenty-nine [days], except Nisan and Tishri. These two [months are fixed] by sighting the crescent. If it was not sighted, then they, too, are made to follow the mentioned order. [ . . . ]

The second group are the supporters of [relying on the month of] Sivan. They are people on whose authority it is reported that they say what Benjamin said about twenty-nine- and thirty-[day months] except that they examine the month of Sivan, which balances out the year. They inclined toward it [i.e., the month of Sivan] only because in their opinion the air in it is clear and without clouds. They seek the crescent in the beginning of it. Then they fix it according to the sighting and they fix the rest of the months that follow it as we said: one month of twenty-nine [days], [then] one month of thirty [days].

Among the supporters of sighting are innovators who advocate the use of the ephemeris [i.e., using the true position of the moon to determine the month]. That is, when they saw some of the differences in the appearance of the crescent in [different] countries, they required the following: if they thought it correct that [the crescent] had been sighted in some clime [i.e., climatic zone], they took it as the beginning of the month. They knew that it may not be visible that evening but would be visible on the morrow after the sun goes down.

St. Petersburg RNL MS Evr.-Arab. 15, fols. 1v–3v.