Musnad Abu Ya'la al-Mawsili 42:247

Zuhayr narrated to us, Rawh ibn Aslam narrated to us, Hammad ibn Salamah narrated to us, from Ali ibn Zayd, from Abu Nadrah, from Abu Sa’id al-Khudri: That the Messenger of Allah (peace and blessings of Allah be upon him) said to Ibn Sayyad, "What do you see?" He said, "I see a throne upon the water of the sea, and around it are snakes." The Messenger of Allah (peace and blessings of Allah be upon him) said, "He has seen the throne of Iblis."