Musnad Ahmad 30:3090

Muhammad ibn Ja'far narrated to us, he said: Shu'bah narrated to us, from Sulayman, and Abu Ahmad, he said: Sufyan narrated to us, from al-A'mash, from Dhakwan, from Abu Hurayrah, from the Prophet, may Allah bless him and grant him peace, that he said: "For the interior of one of you to be filled with pus until it consumes him is better for him than that it be filled with poetry."