Sunan Ibn Majah 762
It was narrated from Anas that:
The Prophet saw some sputum in the prayer direction of the mosque and he became so angry that his face turned red. Then a woman from among the Ansar came and scraped it off, and put some Khaluq on that spot. The Messenger of Allah said: "How good this is."
حَدَّثَنَا مُحَمَّدُ بْنُ طَرِيفٍ، حَدَّثَنَا عَائِذُ بْنُ حَبِيبٍ، عَنْ حُمَيْدٍ، عَنْ أَنَسٍ، أَنَّ النَّبِيَّ ـ صلى الله عليه وسلم ـ رَأَى نُخَامَةً فِي قِبْلَةِ الْمَسْجِدِ فَغَضِبَ حَتَّى احْمَرَّ وَجْهُهُ فَجَاءَتْهُ امْرَأَةٌ مِنَ الأَنْصَارِ فَحَكَّتْهَا وَجَعَلَتْ مَكَانَهَا خَلُوقًا فَقَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ ‏
"‏ مَا أَحْسَنَ هَذَا ‏"‏ ‏.‏