Sayyiduna Anas (may Allah be pleased with him) narrates: Whenever the Prophet Muhammad (peace and blessings be upon him) fought against any people, he would not begin the battle until the break of dawn. He (peace be upon him) would assess the situation; if he heard the call to prayer (adhan) from there, he would not attack them, but if he did not hear the adhan, he would attack them. The narrator says: We set out towards Khaybar and reached there at night. When morning came and the Prophet (peace and blessings be upon him) did not hear the adhan there, he mounted his ride and I rode behind Sayyiduna Abu Talha (may Allah be pleased with him). My feet were touching the blessed feet of the Prophet (peace and blessings be upon him). The people came out (of the fort) with their baskets and shovels, and when they saw the Prophet (peace and blessings be upon him), they exclaimed: "Muhammad has come! By Allah, Muhammad has come and the army is with him!" When the Prophet (peace and blessings be upon him) saw them, he said: "Allahu Akbar! Allahu Akbar! Khaybar is destroyed. When we descend into the field of a people, then evil is the morning for those who have been warned."