Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
tirmidhi:689Aḥmad b. Manīʿ > Yaḥyá b. Zakariyyā b. Abū Zāʾidah > ʿĪsá b. Dīnār from his father > ʿAmr b. al-Ḥārith b. Abū Ḍirār > Ibn Masʿūd

"What I fasted with the Prophet that was twenty-nine (days), was more than what we fasted that was thirty." (He said): There are narrations on this topic from ʿUmar, Abu Hurairah, ʿA'isha, Saʿd bin Abi Waqqas, Ibn ʿAbbas, Ibn ʿUmar, Anas, Jabir, Umm Salamah, Abu Bakrah, that the Prophet ﷺ said: "The month is twenty nine (days)."  

الترمذي:٦٨٩حَدَّثَنَا أَحْمَدُ بْنُ مَنِيعٍ حَدَّثَنَا يَحْيَى بْنُ زَكَرِيَّا بْنِ أَبِي زَائِدَةَ أَخْبَرَنِي عِيسَى بْنُ دِينَارٍ عَنْ أَبِيهِ عَنْ عَمْرِو بْنِ الْحَارِثِ بْنِ أَبِي ضِرَارٍ عَنِ ابْنِ مَسْعُودٍ قَالَ

مَا صُمْتُ مَعَ النَّبِيِّ ﷺ تِسْعًا وَعِشْرِينَ أَكْثَرُ مِمَّا صُمْنَا ثَلاَثِينَ قَالَ وَفِي الْبَابِ عَنْ عُمَرَ وَأَبِي هُرَيْرَةَ وَعَائِشَةَ وَسَعْدِ بْنِ أَبِي وَقَّاصٍ وَابْنِ عَبَّاسٍ وَابْنِ عُمَرَ وَأَنَسٍ وَجَابِرٍ وَأُمِّ سَلَمَةَ وَأَبِي بَكْرَةَ أَنَّ النَّبِيَّ ﷺ قَالَ الشَّهْرُ يَكُونُ تِسْعًا وَعِشْرِينَ