arise at their beginnings, they would serve as measures of time for less than one-thirtieth of people’s affairs.

Moreover, if a month is the interval between two new moons, then that interval is exactly equal to the interval between the middle of one month and the middle of the next. This equality is self-evident, and distinguishing between them is wholly arbitrary.

Furthermore, who determined that a month reckoned by counting days must be thirty days, when the Prophet—may Allah bless him and grant him peace—said:

“The month is like this, and this, and this,” folding in his thumb the third time.

We know that half the months of the year have thirty days and half have twenty-nine. Moreover, Muslims generally, in their worship and dealings, reckon an obligation deferred for a year as follows: if its term begins with the new moon of Muharram, it ends with the new moon of Muharram, at the close of Dhū al-Hijjah. If it begins on the tenth of Muharram, it likewise ends on the tenth of Muharram. Muslims know no other practice and base their reckoning solely upon it. Whoever proceeds to add a day because the first month was short has altered the familiar practice that comes naturally to them and introduced something alien that they do not recognize.

It is thus clear that this is an error on the part of those jurists who supposed it to be correct. We have drawn attention to it so that people may avoid falling into it and understand the true meaning of His words:

“Say, ‘They are measures of time for people.’”

This generality holds without exception and is of great significance: nothing is excluded from it.