Musnad Ahmad 30:2699

Hajjaj narrated to us, Laith narrated to us, Sa'id ibn Abi Sa'id narrated to us, from Abu Hurairah, who said: When Khaybar was conquered, a sheep containing poison was gifted to the Messenger of Allah, may Allah bless him and grant him peace. The Messenger of Allah, may Allah bless him and grant him peace, said: "Gather for me those who are here of the Jews." So they were gathered for him. The Messenger of Allah, may Allah bless him and grant him peace, said to them: "I am going to ask you about something, so will you tell me the truth about it?" They said: "Yes, O Abu al-Qasim." The Messenger of Allah, may Allah bless him and grant him peace, said to them: "Who is your father?" They said: "Our father is so-and-so." The Messenger of Allah, may Allah bless him and grant him peace, said: "Rather, you have lied; your father is so-and-so." They said: "You have spoken the truth and acted righteously." He said to them: "Will you tell me the truth about something I ask you about?" They said: "Yes, O Abu al-Qasim, and if we lie to you, you will know our lie just as you knew it regarding our father." The Messenger of Allah, may Allah bless him and grant him peace, said: "Who are the people of the Fire?" They said: "We will be in it for a little while, then you will succeed us in it." The Messenger of Allah, may Allah bless him and grant him peace, said to them: "We will never succeed you in it ever." Then he said to them: "Will you tell me the truth about something I ask you about?" They said: "Yes, O Abu al-Qasim." He said to them: "Did you put poison in this sheep?" They said: "Yes." He said: "What compelled you to do that?" They said: "We wanted, if you were a liar, to be rid of you, and if you were a prophet, it would not harm you."