سُنَنُ ابْنِ مَاجَهْ
Sunan Ibn Majah 2061
The Chapters on Divorce
Swearing to forego marital relations with one’s wife
حَدَّثَنَا أَحْمَدُ بْنُ يُوسُفَ السُّلَمِيُّ، حَدَّثَنَا أَبُو عَاصِمٍ، عَنِ ابْنِ جُرَيْجٍ، عَنْ يَحْيَى بْنِ عَبْدِ اللَّهِ بْنِ مُحَمَّدِ بْنِ صَيْفِيٍّ، عَنْ عِكْرِمَةَ بْنِ عَبْدِ الرَّحْمَنِ، عَنْ أُمِّ سَلَمَةَ، أَنَّ رَسُولَ اللَّهِ ـ صلى الله عليه وسلم ـ آلَى مِنْ بَعْضِ نِسَائِهِ شَهْرًا فَلَمَّا كَانَ تِسْعَةً وَعِشْرِينَ رَاحَ أَوْ غَدَا . فَقِيلَ يَا رَسُولَ اللَّهِ إِنَّمَا مَضَى تِسْعٌ وَعِشْرُونَ . فَقَالَ الشَّهْرُ تِسْعٌ وَعِشْرُونَ .
It was narrated from Umm Salamah that: the Messenger of Allah (ﷺ) swore to keep away from some of his wives for a month. On the twenty-ninth day, in the evening or the morning, it was said: "O Messenger of Allah, only twenty-nine days have passed." He said: "The month is twenty-nine days."
Sunan Ibn Majah, 2061Sahih (Darussalam)