Sahih Bukhari Volume 4, Book 52, Hadith Number 318.
Narated By Anas bin Malik : We were in the company of the Prophet while returning from ‘Usfan, and Allah’s Apostle was riding his she-camel keeping Safiya bint Huyay riding behind him. His she-camel slipped and both of them fell down. Abu Talha jumped from his camel and said, “O Allah’s Apostle! May Allah sacrifice me for you.” The Prophet said, “Take care of the lady.” So, Abu Talha covered his face with a garment and went to Safiya and covered her with it, and then he set right the condition of their shecamel so that both of them rode, and we were encircling Allah’s Apostle like a cover. When we approached Medina, the Prophet said, “We are returning with repentance and worshipping and praising our Lord.” He kept on saying this till he entered Medina.