Muwatta Malik #503

Malik related to me from Nuaym ibn Abdullah ibn al-Mujmir from AIi ibn Yahya az-Zuraqi from his father that Rifaa ibn Rafi said, "One day we were praying behind the Messenger of Allah, may Allah bless him and grant him peace, when the Messenger of Allah, may Allah bless him and grant him peace, raised his head from ruku and said, 'Allah hears the one who praises Him' (Sami Allahu liman hamidah). A man behind him said, 'Our Lord, praise belongs to you - blessed, pure and abundant praise' (Rabbana wa laka'l hamd, hamdan kathiran tayiban mubarakan fihi). When the Messenger of Allah, may Allah bless him and grant him peace, had finished, he said, 'Who was it who spoke just now?' The man said, 'I did, Messenger of Allah,' and the Messenger of Allah, may Allah bless him and grant him peace, said, 'I saw more than thirty angels rushing to it to see which one of them would record it first.' "