Sunan Abi Dawud, Book 1, Hadith 313 (USC-MSA) ⓘ

Narrated Woman of Banu Ghifar: Umayyah, daughter of AbusSalt, quoted a certain woman of Banu Ghifar, whose name was mentioned to me, as saying: The Messenger of Allah made me ride behind him on the rear of the camel saddle. By Allah, the Messenger of Allah got down in the morning. He made his camel kneel down and I came down from the back of his saddle. There was a mark of blood on it (saddle) and that was the first menstruation that I had. I stuck to the camel and felt ashamed. When the Messenger of Allah saw what had happened to me and saw the blood, he said: Perhaps you are menstruating. I said: Yes. He then said: Set yourself right (i.e. tie some cloth to prevent bleeding), then take a vessel of water and put some salt in it, and then wash the blood from the back of the saddle, and then return to your mount. When the Messenger of Allah conquered Khaybar, he gave us a portion of the booty. Whenever the woman became purified from her menses, she would put salt in water. And when she died, she left a will to put salt in the water for washing her (after death).

حَدَّثَنَا مُحَمَّدُ بْنُ عَمْرٍو الرَّازِيُّ، حَدَّثَنَا سَلَمَةُ، - يَعْنِي ابْنَ الْفَضْلِ - أَخْبَرَنَا مُحَمَّدٌ، - يَعْنِي ابْنَ إِسْحَاقَ - عَنْ سُلَيْمَانَ بْنِ سُحَيْمٍ، عَنْ أُمَيَّةَ بِنْتِ أَبِي الصَّلْتِ، عَنِ امْرَأَةٍ، مِنْ بَنِي غِفَارٍ قَدْ سَمَّاهَا لِي قَالَتْ أَرْدَفَنِي رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى حَقِيبَةِ رَحْلِهِ - قَالَتْ - فَوَاللَّهِ لَمْ يَزَلْ رَسُولُ اللَّهِ صلى الله عليه وسلم إِلَى الصُّبْحِ فَأَنَاخَ وَنَزَلْتُ عَنْ حَقِيبَةِ رَحْلِهِ فَإِذَا بِهَا دَمٌ مِنِّي فَكَانَتْ أَوَّلَ حَيْضَةٍ حِضْتُهَا - قَالَتْ - فَتَقَبَّضْتُ إِلَى النَّاقَةِ وَاسْتَحْيَيْتُ فَلَمَّا رَأَى رَسُولُ اللَّهِ صلى الله عليه وسلم مَا بِي وَرَأَى الدَّمَ قَالَ ‏"‏ مَا لَكِ لَعَلَّكِ نُفِسْتِ ‏"‏ ‏.‏ قُلْتُ نَعَمْ ‏.‏ قَالَ ‏"‏ فَأَصْلِحِي مِنْ نَفْسِكِ ثُمَّ خُذِي إِنَاءً مِنْ مَاءٍ فَاطْرَحِي فِيهِ مِلْحًا ثُمَّ اغْسِلِي مَا أَصَابَ الْحَقِيبَةَ مِنَ الدَّمِ ثُمَّ عُودِي لِمَرْكَبِكِ ‏"‏ ‏.‏ قَالَتْ فَلَمَّا فَتَحَ رَسُولُ اللَّهِ صلى الله عليه وسلم خَيْبَرَ رَضَخَ لَنَا مِنَ الْفَىْءِ - قَالَتْ - وَكَانَتْ لاَ تَطَّهَّرُ مِنْ حَيْضَةٍ إِلاَّ جَعَلَتْ فِي طَهُورِهَا مِلْحًا وَأَوْصَتْ بِهِ أَنْ يُجْعَلَ فِي غُسْلِهَا حِينَ مَاتَتْ ‏.‏