Tafarrud as a cause of illah on the basis of 'Ilal al-Tirmidhî al-Kabîr

When a transmitter is the only person who narrates a certain tradition, this is called "tafarrud" in the science of hadith and scholars of this area have been suspicious of that position. Tafarrud has been a significant element in determining ilal al-hadith and there are many traditions in the books of ilal that were determined to be defective because of tafarrud. There is an agreement among the scholars of hadith that it is not possible to accept the tafarrud (isolation) of a weak transmitter whereas it is not also possible to assert anything certain about the tafarrud of a reliable one. Some isolated traditions narrated by reliable transmitters were regarded as sahîh by hadith scholars, while some others were refused because of their deficiencies. When the latter is analyzed deeply, it is possible to say that the tafarrud of a reliable transmitter is not solely regarded as a reason for the deficiency of a hadith; there are some other factors that co-exist with the isolation of the narrator, as a result of which the hadith is regarded as mu'allal (deficient). In this study, the issue of the tafarrud of a reliable transmitter is discussed on the basis of 'Ilal al-Tirmidhî al-kabîr, by analyzing the ahadith which Bukharî regarded as deficient because of the tafarrud of the narrator and in relation with this, the conditions which require the rejection of the tafarrud of the transmitter are detected. Key Words: Illah, tafarrud, isolation, reliable transmitter, 'Ilal al-Tirmidhî al-kabîr, al-Tirmidhî, al-Bukharî