Narrated Abu Musa Al-Ash`ari: We were in the company of Allah's Apostle (during Hajj). Whenever we went up a high place we used to say: None has the right to be worshipped but Allah, and Allah is Greater, and our voices used to rise, so the Prophet said, O people! Be merciful to yourselves (i.e. don't raise your voice), for you are not calling a deaf or an absent one, but One Who is with you, no doubt He is All-Hearer, ever Near (to all things).