'Aishah said:

Asma' asked the Prophet ﷺ and then narrated the rest of the tradition to the same effect. He (the Prophet) said: "a musk-scented piece of cloth." She (Asma') said: How should I purify with it ? He said: By glory of Allah ! Purify with it, and he covered his face with the cloth. This version also adds: "She asked about the washing because of sexual defilement." He said: Take your water and purify yourself as best as possible. Then pour water over yourself. 'Aishah said: The best of the women are the women of the Ansar. Shyness would not prevent them from inquiring about religion and from acquiring deep understanding in it.

حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ الْعَنْبَرِيُّ، أَخْبَرَنِي أَبِي، عَنْ شُعْبَةَ، عَنْ إِبْرَاهِيمَ، - يَعْنِي ابْنَ مُهَاجِرٍ - عَنْ صَفِيَّةَ بِنْتِ شَيْبَةَ، عَنْ عَائِشَةَ، أَنَّ أَسْمَاءَ، سَأَلَتِ النَّبِيَّ ﷺ بِمَعْنَاهُ قَالَ " فِرْصَةً مُمَسَّكَةً " . قَالَتْ كَيْفَ أَتَطَهَّرُ بِهَا قَالَ " سُبْحَانَ اللَّهِ تَطَهَّرِي بِهَا وَاسْتَتِرِي بِثَوْبٍ " . وَزَادَ وَسَأَلَتْهُ عَنِ الْغُسْلِ مِنَ الْجَنَابَةِ فَقَالَ " تَأْخُذِينَ مَاءَكِ فَتَطَهَّرِينَ أَحْسَنَ الطُّهُورِ وَأَبْلَغَهُ ثُمَّ تَصُبِّينَ عَلَى رَأْسِكِ الْمَاءَ ثُمَّ تَدْلُكِينَهُ حَتَّى يَبْلُغَ شُئُونَ رَأْسِكِ ثُمَّ تُفِيضِينَ عَلَيْكِ الْمَاءَ " . قَالَ وَقَالَتْ عَائِشَةُ نِعْمَ النِّسَاءُ نِسَاءُ الأَنْصَارِ لَمْ يَكُنْ يَمْنَعُهُنَّ الْحَيَاءُ أَنْ يَسْأَلْنَ عَنِ الدِّينِ وَيَتَفَقَّهْنَ فِيهِ .