僧羯磨 3.101

3.101

六念法（依《僧祇》云：）第一念：（謂知日數，月之大小、黑白。稱云：）此月大（月小稱小），白月一日乃至十五日。（黑月應云：）黑月一日乃至十四、十五日。（西方本制，月有黑白，白月純大，黑有小大；此土，月以三十日為。故作念者，通知大小，即應此方立其月法；別言黑白一二日等，復順西方本制月日。）

The Procedure of the Six Recollections (According to the Mahāsāṃghika [Vinaya]:) The first recollection: (meaning to know the number of days, whether the month is long or short, and the dark or bright fortnight. One declares, saying:) 'This month is long (if the month is short, declare short), from the first day to the fifteenth day of the bright fortnight.' (For the dark fortnight, one should say:) 'From the first day to the fourteenth or fifteenth day of the dark fortnight.' (According to the original system of the Western Regions, months have dark and bright fortnights; the bright fortnight is exclusively long, while the dark has both short and long; in this land, a month consists of thirty days. Therefore, in practicing the recollection, commonly knowing long and short conforms to the calendar system established in this land, while specifying the first, second, etc., days of the dark and bright fortnights accords with the original month and day system of the Western Regions.)