Musnad Ahmad 788:121

Muhammad ibn Ja'far narrated to us, Shu'bah narrated to us, from 'Asim, from Abu 'Uthman, from Abu Musa, that they were with the Messenger of Allah, peace and blessings of Allah be upon him, on a journey. They raised their voices in supplication, so the Messenger of Allah, peace and blessings of Allah be upon him, said: "You are not calling upon one who is deaf, nor one who is absent. You are calling upon One who is near, Responsive; He hears your supplication and responds." Then he said: "O 'Abdullah ibn Qays—or O Abu Musa—shall I not guide you to a treasure from the treasures of Paradise? 'There is no power and no strength except by Allah' (La hawla wa la quwwata illa billah)."