Sahih al-Bukhari 6212

Musaddad narrated to us: Yahya narrated to us, from Shubah, who said: Qatadah told me, from Anas ibn Malik, who said: There was an alarm in Medina, so the Messenger of Allah, peace and blessings be upon him, rode a horse belonging to Abu Talhah. He said, ‘We saw nothing, and we found it to be a sea.’