Jāmi` at-Tirmidhī is a collection of hadīth compiled by Imām Abu `Isa Muḥammad at-Tirmidhī (rahimahullāh). His collection is unanimously considered to be one of the six canonical collections of ḥadīth (Kutub as-Sittah) of the Sunnah of the Prophet ﷺ. It contains roughly 4400 hadīth (with repetitions) in 46 books.
This collection is titled Al-Jami` al-Mukhtasar min as-Sunan `an Rasulu Allāh wa Ma`rifatu as-Sahih wa al-Ma`lul wa ma `alaihi al-`amal otherwise known as Jami` at-Tirmidhi.
Author
He is Abū ‛Īsa Muḥammad ibn ‛Īsa ibn Sawrah ibn Mūsa ibn al Ḍaḥḥāk al-Sulamī at-Tirmidhī (209-279 AH/824–892 AD). Imam at-Tirmidhi was born in the year 209 A.H. during the reign of the Abbasid Khalifa Ma'mun al-Rashid. The Abbasid Caliphate, despite its brilliant contributions to Islam, brought along with it many problems. Greek philosophy had a free flow into the Islamic world. This was fully sanctioned by the government until eventually it declared the Mu`tazila school of thought as the state religion. Anyone who opposed the Mu`tazila school of thought would be opposing the state. With the influence of Greek philosophy among the people, many Muslims began attempting to reconcile between (this brand of) reason and revelation. As a result many deviations were introduced and many innocent and weak Muslims were led away from Allāh and His Prophet ﷺ). Many scholars of Islam had come to the fore in order to defend the Shari`ah. Forgeries and interpolations in Ḥadīth by rulers who wished to fulfill their personal motives were common. In the first century `Umar bin Abdul `Aziz 
initiated a movement for the compilation of the ḥadīth of the Prophet ﷺ as there was a fear of them being lost. A number of scholars of Islam undertook this task, six among them stand taller than the rest. One of the six was Imam Abu `Isa Muhammed ibn `Isa at-Tirmidhi.
Having grown up in an environment of learning and possessing many great qualities naturally drove Imam Tirmidhi to dedicate his life totally towards the field of Ḥadīth. He obtained his basic knowledge at home and later travelled to far off lands in search of knowledge of this science. He studied Ḥadīth under great personalities such as Imam al-Bukhari, Imam Muslim and Imam Abu Dawud. In some narrations Imam al-Bukhari and Imam Muslim are his students as well. Once Imam al-Bukhari mentioned to him "I have benefited more from you than you have benefitted from me." Musa ibn `Alaq once said: "When Imam al-Bukhari passed away, he left no one in Khurasan who compared with Abu `Isa Tirmidhi in knowledge, memory, piety and abstinence." Imam at-Tirmidhi said that he compiled this book and presented it to the learned scholars of Hijaz, Iraq and Khurasan and they were pleased with it.
His Memory
Imam Tirmidhi had an exceptionally remarkable memory. If he heard something once he never forgot it. Once on his way to Makkah, Imam Tirmidhi met a scholar of ḥadīth (muhaddith) from whom he had previously copied two chapters of ḥadīth. Thinking that he had the notes with him he asked the scholar if he would allow him to read out these two chapters so that he could correct any errors. After realizing that he did not have those notes with him he took a blank piece of paper and read out the entire two parts from memory. When the muhaddith realized what he was doing he rebuked Imam Tirmidhi saying: "Have you no shame, why are you wasting my time." Imam Tirmidhi assured him that he had committed all the aḥadīth to memory. The scholar was not convinced, even though Imam Tirmidhi had recited all the ḥadīth from memory. Imam Tirmidhi requested him to recite to him some other ḥadīth. The scholar recited forty aḥadīth, which Imam Tirmidhi then repeated without making a single error, thus showing his remarkable power of committing ḥadīth to memory.His Works
Many books of ḥadīth were compiled before Imam Tirmidhi decided to compile his Jami`. Dawud Tayalisi and Ahmed ibn Hanbal had compiled books consisting of both authentic and weak ḥadīth. Later Imam al-Bukhari compiled his Sahih and omitted all weak narrations from it. His main objective was to derive masa'il (laws) from the relevant ḥadīth. Later Imam Muslim compiled his book with a primary focus on the isnad (different chains of narrators). Imam an-Nasa'i's aim was to mention the discrepancies of the ḥadīth whilst Abu Dawud prepared a book which became the basis for the fuqaha. Imam at-Tirmidhi combined the styles of al-Bukhari, Muslim, Abu Dawud and an-Nasa'i by mentioning discrepancies regarding the narrators and also making his compilation a basis for jurists.His Students
Imam Tirmidhi had a large number of students from all over the world. The most famous amongst them were Haytham ibn Kulaib, Abul Abbaas and Muḥammad ibn Ahmad Shah Abdul `Aziz, who describes Imam Tirmidhi in the following words: "His memory was unique and his piety and fear of Allāh ta'la was of a very high caliber. He would cry so much out of the fear of Allāh, that towards the end of his life he lost his sight." According to Ibn Taymiyya and Shah Waliullah, Imam Tirmidhi was an independent jurist (mujtahid).His Death
In the year 279 A.H. in a village called Bawag at the age of 70 , Imam Tirmidhi passed away.Methods of Classification and Annotation
According to the commentators of Al-Jami`, Imam Tirmidhi maintained the following conditions throughout the compilation of his book:- He never narrated ḥadīth from those who fabricated ḥadīth.
- Tahir Muqaddisi mentions that al-Jami` ut-Tirmidhi contains four types of ḥadīth:
- Those aḥadīth that conform with the conditions of al-Bukhari and Muslim.
- Those aḥadīth that conform with the conditions of Abu Dawud and Nasa'i.
- Those aḥadīth that have certain discrepancies either in the sanad or matan.
- Those weak ḥadīth that some fuqaha have relied on.
- Imam Tirmidhi accepts a ḥadīth which is narrated with the word `an provided both the narrators are contemporaries.
- After mentioning a weak ḥadīth, he explains the state of its weakness.
- A mursal ḥadīth is accepted by Imam Tirmidhi when a chain of narrators which is not broken supports it.
The status of Jami` at-Tirmidhi is among the six authentic books of ḥadīth. It has been categorized as fifth amongst the six most authentic books of ḥadīth. According to the most preferred opinion, al-Bukhari enjoys the highest status, followed by Muslim, Abu Dawud, Nasai, Tirmidhi and Ibn Majah respectively. Haji Khalifa in al-Kashf al-Dhunoon has categorized Tirmidhi in third position. Al-Dhahabi has written that Tirmidhi in actual fact should be holding the third position, but due to him bringing weak narrators like Kalbi and Masloob its status has dropped. However, looking at the manner in which he set out his book it seems that Haji Khalifa's opinion is best.