Al-Muwatta Hadith 54.33

Malik related to me from Safiyy, the mawla of Ibn Aflah that Abu's-Saib, the mawla of Hisham ibn Zuhra said, "I went to Abu Said al-Khudri and found him praying. I sat to wait for him until he finished the prayer. I heard a movement under a bed in his room, and it was a snake. I stood up to kill it, and Abu Said gestured to me to sit. When he was finished he pointed to a room in the house and said, 'Do you see this room?' I said, 'Yes.' He said, 'There was a young boy in it who had just got married. He went out with the Messenger of Allah, may Allah bless him and grant him peace, to al-Khandaq, (the ditch which the muslims dug in the 5th year of the Hijra to defend Madina against the Quraysh and their allies). When he was there, the youth came and asked his permission, saying, "Messenger of Allah. Give me permission to return to my family." The Messenger of Allah, may Allah bless him and grant him peace, gave him permission and said, "Take your weapons with you, for I fear the Banu Quraydha tribe. They may harm you." The youth went to his family and found his wife standing between the two doors. He lifted his spear to stab her as jealousy had been aroused in him. She said, "Don't be hasty until you go in and see what is in your house." He entered and found a snake coiled up on his bed. He transfixed it with his spear and then went out with it and pitched it into the house. The snake stirred on the end of the spear and the youth fell dead. No one knew which of them died first, the snake or the youth. That was mentioned to the Messenger of Allah, may Allah bless him and grant him peace, and he said, "There are jinn in Madina who have become muslim. When you see one of them, call out to it for three days. If it appears after that, then kill it, for it is a shaytan." "'