Mukhtasar Bukhari

Narrated Abu Musa Al-Ash'ari (may Allah be pleased with him): When the Messenger of Allah (peace and blessings of Allah be upon him) attacked Khaybar, (on the way) the people climbed a high place and began to call out loudly: "Allahu Akbar, Allahu Akbar, La ilaha illallah." So the Prophet (peace and blessings of Allah be upon him) said: "Be gentle with yourselves (and do not shout), for you are not calling upon one who is deaf or absent, but you are calling upon the One who hears and is very near, and He is with you." (At that time) I was right behind the riding animal of the Messenger of Allah (peace and blessings of Allah be upon him). He heard me reciting: "La hawla wa la quwwata illa billah." Then he said: "O Abdullah bin Qais!" (This is the real name of Abu Musa Al-Ash'ari, may Allah be pleased with him.) I said: "Labbaik, O Messenger of Allah! (I am present, O Messenger of Allah!)" So the Prophet (peace and blessings of Allah be upon him) said: "Shall I not tell you a phrase which is one of the treasures of Paradise?" I said: "Certainly, O Messenger of Allah! Please tell me, may my parents be sacrificed for you." The Prophet (peace and blessings of Allah be upon him) said: "(That phrase is) La hawla wa la quwwata illa billah."