This is an extract from the book Al-Waadih Fee Usool ul-Fiqh by Muhammad Hussein Abdullah available to purchase from Maktaba Islamia . There are three categories of hadith in respect to their As-Sihhah (soundness) and Ad-Da’f (weakness). These are Saheeh, Hasan and Da’eef. In respect to the Sanad (chain) there are also three categories. These are Al-Mutawaatir, Al-Mash’hoor and Khabar Al-Aahaad. Al-Hadeeth As-Saheeh (Sound) This is the Hadeeth in which its Isnaad (chain) connects the transmission of the ‘Adl Ad-Daabit from the ‘Adl Ad-Daabit until its end and is not Shaadh or Mu’allal. Al-‘Adl (the just): As-Sudooq At-Taqi (The honest person who fears Allah and obeys Him). Ad-Daabit (the precise): Known for his astuteness and not being careless or inattentive. Until its end: The Sanad (chain) connects to the Messenger ﷺ. Not Shaadh (irregular) or without Shudhoodh (irregularity): That it does not go against the Thiqqah (a trustworthy narrator) stronger than
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