Muwatta Malik #1789
Dress
The Arabic includes the chain of narration (sanad) and the collector's commentary; the English translation shows the Prophet's words only.
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ أَبِي بَكْرِ بْنِ نَافِعٍ، عَنْ أَبِيهِ، نَافِعٍ مَوْلَى ابْنِ عُمَرَ عَنْ صَفِيَّةَ بِنْتِ أَبِي عُبَيْدٍ، أَنَّهَا أَخْبَرَتْهُ عَنْ أُمِّ سَلَمَةَ، زَوْجِ النَّبِيِّ صلى الله عليه وسلم أَنَّهَا قَالَتْ حِينَ ذُكِرَ الإِزَارُ فَالْمَرْأَةُ يَا رَسُولَ اللَّهِ قَالَ " تُرْخِيهِ شِبْرًا " . قَالَتْ أُمُّ سَلَمَةَ إِذًا يَنْكَشِفُ عَنْهَا . قَالَ " فَذِرَاعًا لاَ تَزِيدُ عَلَيْهِ " .
Yahya related to me from Malik from Abu Bakr ibn Nafi from his
father Nafi, the mawla of Ibn Umar that Safiyya bint Abi Ubayd
informed him that Umm Salama, the wife of the Prophet, may Allah bless
him and grant him peace, said that when the lower garment of women was
mentioned to the Messenger of Allah, he said, "She lets it down a
handspan." Umm Salama said, "If it leaves her uncovered?" He said,
"Then the length of a forearm and let her not increase it."
About Muwatta Malik
This hadith is #1789 from Muwatta Malik, in the Book of Dress.