4 - Since Imam al-Tirmidhi did not stipulate in his book the inclusion of only authentic hadiths, but rather included in it the authentic, the weak, and the rejected, it became necessary to distinguish their authentic from their defective, and to clarify what may be cited as evidence from what may not, as more than one of the imams called for this, out of sincere counsel to God, His Messenger, and the general body of Muslims. We have therefore undertaken a study of the chain of transmission of every hadith in "al-Jāmiʿ," and have ruled upon it according to what befits its condition—whether authentic, good, or weak—guided by the principles and rules that the masters and critics of hadith established for authenticating narrations, examining chains of transmission, and scrutinizing texts. Indeed, al-Ḥāfiẓ Ibn Ḥajar, may God have mercy on him, mentioned in his "Nukat ʿalā Ibn al-Ṣalāḥ"(1): that in the Sunan there is much that is not suitable for citation as evidence, and that among them there is what is suitable for citation as supporting witness from the narrations of abandoned narrators… Then he said: And when this is established, the path of whoever wishes to cite a hadith from the Sunan, or hadiths from the Musnads, is one and the same, since none of those who compiled them stipulated authenticity or even goodness specifically. So this one who cites evidence—if he is qualified to know the authentic from other than it, he is not permitted to cite a hadith from the Sunan without examining the continuity of its chain and the condition of its narrators, just as he is not permitted to cite a hadith from the Musnads until he has comprehensive knowledge of that. And if he is not qualified for that, then his path is to look into the hadith—if it is in the "Ṣaḥīḥayn" or one of the imams has explicitly stated—

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(1) 1/448.