The word Mudallas comes from the verb dallasa which literally means to hide the defects in goods from a buyer. Technically it refers to the hiding of a defect in the sanad and the beautification of its outer appearance. It may be further subdivided into two other groups: Tadlees as-Sanad and Tadleesash-Shuyookh.
Tadlees as-Sanad 1. The first is the case where a narrator, narrates something which he did not hear from someone whom he studied under in an ambiguous fashion. He does not openly claim to have heard it from his teacher but only implies it by using the phrase "he said" or "from". E.g. Ali ibn Khashram said that Ibn Uyaynah related to us from az-Zuhri but when he was asked, "Did you hear it from az-Zuhri?" he replied, "Abdur-Razzaq informed me from Muammar from az-Zuhri."
In this example Ibn Uyaynah had deleted two narrators between himself and az-Zuhri. "Ubaydullah ibn Sad informed us (saying), my uncle informed us (saying), my father informed us from Ibn Ishaq from Muhammad ibn Amr ibn Ata from Dhakwan, the freed slave of Aishah (RA), that she informed him that the Messenger of Allah (salallahu alayhi wa sallam) used to pray after Asr prayers and forbid it, and he used to fast for twenty-four hours and forbid continual fasting." (Abu Dawud) The narrators of this hadith are reliable. However, Ibn lshaq, whose name was Muhammad ibn Ishaq ibn Yassar was a known mudallis and he narrated this hadith from Muhammad ibn Amr using the phrase an(from) without clearly indicating that he actually heard it from him.
2. The other form is where a Raawi (narrator) narrates from his teacher deleting from the chain a weak narrator between two strong narrators who met each other by using ambiguous terminology. E.g. Abu Hatim collected the following hadith in which his father said Ishaq ibn Rahawayh reported from Baqiyah who said that Abu Wahb al-Asadi informed him from Nafifrom Ibn Umar the hadith: "Dont praise a mans Islam until you know what his opinions are." Abu Hatims father said, "This hadith has in it a point which few people realize, Ubaydullah ibn Amr narrated this hadith from Ishaq ibn Farwah from Nafifrom Ibn Umar from the Prophet (salallahu alayhi wa sallam) because Ubaydullah ibn Saqiyah called him Abu Wahb al-Asasi so he would not be spotted when he dropped Ishaq ibn Abi Farwah.
Ubaydullah was considered thiqah (reliable narrator), Ishaq ibn Farwah was weak and Nafiwas strong. This form of tadlees is also called Tadlees at- Taswiyah and is the worst form of tadlees. Scholars like al- Iraqi declared, "Any scholar ~who does Tadlees at- Taswiyah will be dismissed as weak." Among those noted for this practice was al-Waleed ibn Muslim. The most infamous practitioner of this act was Baqiyah ibn al-Waleed.
This article was culled from the publications of Deen Communication Limited