Our companions have deduced a second perspective: that all months are calculated by number (days). This is also the opinion of Ibn bint al-Shafi'i; because if the first is calculated by number, the beginning of the second will be from the middle of a month, so it must be calculated by number, and likewise the third. Our argument is that the term 'month' can refer to the period between two new moons or to thirty days. This is why, if a month is obscured by clouds, it is completed to thirty days. The primary standard is the new moon; if it is possible to use the new moon for calculation, it is used, and if that is impossible, one resorts to the number of days. In this, there is a resolution to what was mentioned regarding the position of Abu Hanifah. As for the deduction we mentioned, it does not necessitate the completion of the first month from the second; it is permissible for its completion to occur from the fourth.
Section: The 'idda is calculated from the hour in which her husband separated from her. If he separated from her at midnight or midday, she counts from that time until the same time, according to the opinion of the majority of scholars. Abu Abd Allah ibn Hamid said: She does not calculate by hours, but rather by the beginning of the night or day. If he divorces her during the day, she counts from the beginning of the night that follows it, and if he divorces her at night, she counts from the beginning of the day that follows it. This is the opinion of Malik; because calculating hours is burdensome, so its consideration is dropped. Our argument is the saying of Allah the Almighty: {Then their period is three months}. It is not permissible to add to this without evidence, and the calculation of hours is possible, either with certainty or as a precaution, so there is no ground for adding to what Allah the Almighty has obligated.
1343 - Issue; he said: (And the slave woman is two months)
(6) In A and M: "they consider". (7) In M: "they return". (8) In M: "it becomes obligatory". (9) In the original: "she counts". (10) In B: "And if". (1) In the original and B: "The narration".