Then he said: The more appropriate course, following the clear path, is to say that it [the Jamiʿ] comprises the hadith organized by chapters, and this is a science in itself; jurisprudence is a second science; the defects of hadith, which includes the clarification of the sound from the weak and the ranks between them, is a third science; names and epithets a fourth; modification and discrediting a fifth; identifying who met the Prophet ﷺ and who did not, among those who reported on his authority in his book, a sixth; and enumerating those who transmitted a given hadith a seventh. These are its general sciences. As for the detailed ones, they are numerous. In sum, its benefit is great and its advantages abundant.

Imam Ibn Sayyid al-Nās al-Yaʿmarī said, commenting on the words of Qāḍī Abū Bakr and Imam Ibn Rushayd: Among what neither of them, nor either one alone, mentioned is what it comprises of irregular narrations—an eighth type—of stopped narrations—a ninth—and of interpolated narrations—a tenth. These types are among the abundant benefits sought from it and derived through it(1).

Al-Dhahabī said: His book "al-Jāmiʿ" demonstrates his deep expertise in this field, in jurisprudence, and in the disagreements of the scholars(2).

Ibn al-Athīr said: Al-Tirmidhī is one of the eminent scholars and distinguished hadith masters, and he has a capable hand in jurisprudence.

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(1) "Al-Nafkh al-Shadhī fī Sharḥ Jāmiʿ al-Tirmidhī" 1/193–194.
(2) "Tārīkh al-Islām," deaths 261–280, p. 460.