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.
tabarani:7035Mūsá b. Hārūn > Marwān b. Jaʿfar > Muḥammad b. Ibrāhīm > Jaʿfar b. Saʿd > Khubayb b. Sulaymān from his father > Samurah b. Jundub

[Machine] The Messenger of Allah ﷺ said, "Indeed, the month does not complete thirty nights." Musa ibn Harun (Aaron) said, meaning that not every month is thirty days, but sometimes it is twenty-nine or twenty-eight.  

الطبراني:٧٠٣٥حَدَّثَنَا مُوسَى بْنُ هَارُونَ ثنا مَرْوَانُ بْنُ جَعْفَرٍ ثنا مُحَمَّدُ بْنُ إِبْرَاهِيمَ ثنا جَعْفَرُ بْنُ سَعْدٍ عَنْ خُبَيْبِ بْنِ سُلَيْمَانَ عَنْ أَبِيهِ عَنْ سَمُرَةَ بْنِ جُنْدُبٍ

أَنَّ رَسُولَ اللهِ ﷺ قَالَ «إِنَّ الشَّهْرَ لَا يَكْمُلُ ثَلَاثِينَ لَيْلَةً» قَالَ مُوسَى بْنُ هَارُونَ مَعْنَاهُ أَنَّهُ لَا يَكْمُلُ كُلُّ شَهْرٍ ثَلَاثِينَ أَيْ أَنَّهُ أَحْيَانًا يَكُونُ تِسْعَةً وَعِشْرِينَ