Muwatta Malik, Book 20, Hadith 729 (In-Book) ⓘ

Yahya related to me from Malik from as-Salt ibn Zubayd from more than one of his family that Umar ibn al-Khattab discovered the smell of perfume while he was at ash-Shajara. Kathir ibn as-Salt was at his side, and Umar asked, "Who is this smell of perfume coming from?", and Kathir said, "From me, amir al-muminin. I matted my hair with perfume and I intended not to shave it.'' Umar said, "Go to a sharaba and rub your head until it is clean," and Kathir did so. Malik explained, "A sharaba is the ditch at the base of a date-palm."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنِ الصَّلْتِ بْنِ زُيَيْدٍ، عَنْ غَيْرِ، وَاحِدٍ، مِنْ أَهْلِهِ أَنَّ عُمَرَ بْنَ الْخَطَّابِ، وَجَدَ رِيحَ طِيبٍ وَهُوَ بِالشَّجَرَةِ وَإِلَى جَنْبِهِ كَثِيرُ بْنُ الصَّلْتِ فَقَالَ عُمَرُ مِمَّنْ رِيحُ هَذَا الطِّيبِ فَقَالَ كَثِيرٌ مِنِّي يَا أَمِيرَ الْمُؤْمِنِينَ لَبَّدْتُ رَأْسِي وَأَرَدْتُ أَنْ لاَ أَحْلِقَ ‏.‏ فَقَالَ عُمَرُ فَاذْهَبْ إِلَى شَرَبَةٍ فَادْلُكْ رَأْسَكَ حَتَّى تُنَقِّيَهُ ‏.‏ فَفَعَلَ كَثِيرُ بْنُ الصَّلْتِ ‏.‏ قَالَ مَالِكٌ الشَّرَبَةُ حَفِيرٌ تَكُونُ عِنْدَ أَصْلِ النَّخْلَةِ ‏.‏