Sahih Muslim | Book 7 | Hadith Number 3199

Narrated by Abu Huraira and Sa'd
Abu Huraira and Sa'd reported Allah's Messenger (way peace be upon him) as saying: O Allah, bless the people of Medina in their mudd, the rest of the hadith being the same, and in It (this is also mentioned): "He who intends to do harm to its people, Allah would efface him just as salt it dissolved in water.