عَنْ أَنَسِ بْنِ مَالِكٍ رَضِيَ اللَّهُ عَنْهُ قَالَ كَانَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ يَدْخُلُ بَيْتَ أُمِّ سُلَيْمٍ وَيَنَامُ عَلَى فِرَاشِهَا وَلَيْسَتْ فِي بَيْتِهَا قَالَ فَأُتِيَتْ يَوْمًا فَقِيلَ لَهَا هَذَا النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ نَائِمٌ عَلَى فِرَاشِكِ قَالَتْ فَجِئْتُ وَذَاكَ فِي الصَّيْفِ فَعَرِقَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ حَتَّى اسْتَنْقَعَ عَرَقُهُ عَلَى قِطْعَةِ أَدَمٍ عَلَى الْفِرَاشِ فَجَعَلْتُ أُنَشِّفُ ذَلِكَ الْعَرَقَ وَأَعْصِرُهُ فِي قَارُورَةٍ فَفَزِعَ وَأَنَا أَصْنَعُ ذَلِكَ فَقَالَ ”مَا تَصْنَعِينَ يَا أُمَّ سُلَيْمٍ“ قُلْتُ يَا رَسُولَ اللَّهِ نَرْجُو بَرَكَتَهُ لِصِبْيَانِنَا قَالَ ”أَصَبْتِ“
It is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) used to visit Sayyida Umm Sulaym (may Allah be pleased with her) and would sleep on her bed. Sometimes it would happen that she was not present at her home. One day, when she came home, she was told that the Noble Prophet (peace and blessings be upon him) was sleeping on her bed, and it was the season of heat. The Noble Prophet (peace and blessings be upon him) perspired so much that his sweat was falling onto a piece of leather on the bed. Sayyida Umm Sulaym (may Allah be pleased with her) says: I began to collect his sweat by squeezing it into a bottle. While I was doing this, the Prophet (peace and blessings be upon him) woke up and said: "Umm Sulaym, what are you doing?" I replied: "O Messenger of Allah! We want to use it as a blessing for our children." The Prophet (peace and blessings be upon him) said: "You are doing right."