1 – Al-Ḥasan narrated, through al-Shaʿbī, from al-Nuʿmān ibn Bashīr, who traced it back to the Prophet (peace and blessings be upon him). He said: “Within the human being there is a small lump of flesh; if it is sound, the whole body is sound, and if it becomes diseased, the whole body becomes diseased. Know well: it is the heart.”