Abu Dawud Book 2, Hadith Number 1521.

Chapter : On seeking pardon and repentance.

Narated By Abu Musa al-Ash’ari : Once we accompanied the Apostle of Allah (PBUH) on a journey. When we reached near Medina, the people began to say aloud: “Allah is most great,” and they raised their voice.

The Apostle of Allah (PBUH) said: O people, you are not supplicating one who is deaf and absent, but you are supplicating One Who is nearer to you than the neck of your riding beast.

The Apostle of Allah (PBUH) then said: AbuMusa, should I not point out to you one of the treasures of Paradise?

I asked: What is that?

He replied: “There is no might and there is no power except in Allah”