Hazrat Abu Musa Ash'ari (may Allah be pleased with him) narrated that when the Messenger of Allah (peace and blessings be upon him) launched a campaign against Khaybar, or as he said, when the Messenger of Allah (peace and blessings be upon him) set out towards Khaybar, (on the way) the people reached a valley and began to say Takbeer in loud voices: "Allahu Akbar, Allahu Akbar, La ilaha illallah" (Allah is the Greatest, Allah is the Greatest, there is no deity except Allah). The Prophet (peace and blessings be upon him) said: Have mercy on yourselves; you are not calling upon one who is deaf or absent. The One whom you are calling is the All-Hearing and very near to you; rather, He is with you. I was riding behind the Messenger of Allah (peace and blessings be upon him) on his mount. When I said "La hawla wa la quwwata illa billah" (There is no power and no strength except with Allah), the Messenger of Allah (peace and blessings be upon him) heard it. He said: Abdullah bin Qais! I said: At your service, O Messenger of Allah! He said: Shall I not tell you a phrase which is one of the treasures of Paradise? I said: Certainly, O Messenger of Allah! May my parents be sacrificed for you. The Messenger of Allah (peace and blessings be upon him) said: That phrase is this: "La hawla wa la quwwata illa billah."