Sahih Muslim

Abdullah b. 'Abbas reported that he said to the Mu'adhdhin on a rainy day:When you have announced"" I testify that there is no god but Allah; I testify that Muhammad is the Messenger of Allah,"" do not say:"" Come to the prayer,"" but make this announcement:"" Say prayer in your houses."" He (the narrator) said that the people disapproved of it. Ibn 'Abbas said: Are you astonished at it? He (the Holy Prophet), who is better than I, did it. Jumu'a prayer is no doubt obligatory, but I do not like that I should (force you) to come out and walk in mud and slippery ground