He was a renowned scholar of Islamic Jurisprudence and hadees shareef. There were numerous guides including Imam Bukharee, Imam Muslim, Imam Abu Daood, under whose guidance he had completed his education. He was famous for his sharp memory.
Imam Tirmizi had and exceptionally remarkable memory. If he heard something once he never forgot it. Once on his way to Makkah, Imam Tirmizi met a scholar of ahadees from whom he had previously copied two chapters of hadees. Thinking that he (Imam Tirmizee) had the notes with him he (scholar) asked him if he would allow him to read out these two chapters so that he could correct any errors. As Imam Tirmizi 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 scholar realized what he was doing he rebuked Imam Tirmizee. Imam Tirmizee assured him that he had committed all the ahadees to memory. The scholar was not yet convinced.
Imam Tirmizee requested him to recite to him some other hadees. The scholar recited forty ahadees, which Imam Tirmizee repeated without making a single error, thus showing his remarkable power of committing hadees to memory.