Narrated 'Aisha:(the wife of the Prophet) We set out with Allahs Apostle on one of his journeys till we reached Al-Baida' or Dhatul-Jaish, a necklace of mine was broken (and lost). Allah's Apostle stayed there to search for it, and so did the people along with him. There was no water at that place, so the people went to Abu- Bakr As-Siddiq and said, "Don't you see what 'Aisha has done? She has made Allah's Apostle and the people stay where there is no water and they have no water with them." Abu Bakr came while Allah's Apostle was sleeping with his head on my thigh, He said, to me: "You have detained Allah's Apostle and the people where there is no water and they have no water with them.
So he admonished me and said what Allah wished him to say and hit me on my flank with his hand. Nothing prevented me from moving (because of pain) but the position of Allah's Apostle on my thigh. Allah's Apostle got up when dawn broke and there was no water. So Allah revealed the Divine Verses of Tayammum. So they all performed Tayammum. Usaid bin Hudair said, "O the family of Abu Bakr! This is not the first blessing of yours." Then the camel on which I was riding was caused to move from its place and the necklace was found beneath it.