“Allahu Akbar, Allahu Akbar, Ashhadu an la ilaha illallah, Ashhadu anna Muhammadan Rasulullah (Allah is the Most Great, Allah is Most Great, I bear witness that none has the right to be worshipped but Allah, I bear witness that Muhammad is the Messenger of Allah).” Then he (Ibn ‘Abbas) said: “Proclaim to the people that they should pray in their houses.” The people said to him: “What is this that you have done?” He said: “One who is better than me did that. Are you telling me that I should bring the people out of their houses and make them come to me wading through the mud up to their knees?”
Sunan Ibn Majah Book 5, Hadith 137