سنن النسائي

It was narrated that 'Ammar said: "The Messenger of Allah (ﷺ) stopped to rest at the end of the night in Uwlat Al-Jaish. His wife 'Aishah was with him and her necklace of Zifar beads [1] broke and fell. The army was detained looking for that necklace of hers until the break of the light of dawn and the people had no water with them. Abu Bakr got angry with her and said: 'You have detained the people and they do not have any water.' Then Allah the Mighty and Sublime revealed the concession allowing Tayammum with clean earth. So the Muslims got up with the Messenger of Allah (ﷺ) and struck with their hands, then they raised their hands and did not strike them together to knock off any dust, then they wiped their faces and arms up to the shoulders, and from the inner side of their of their arms up to the armpits." [1] Black and white Yemeni beads.