Imam Tirmidhi was a man of strong memory. James Robson mentions an interesting story which illustrates his power of committing traditions to memory. Once on the way to Makka, Imam Tirmidhi met a traditionist from whose traditions he had previously copied out two parts. Thinking he had these notes with him, he questioned the traditionist about the traditions, which he had noted, but discovered that instead of his notes, he had brought some blank sheets of paper. Nonetheless he continued his questions with these sheets in his hand, and after a while the traditionist noticed that they were blank and rebuked him, whereupon Imam Tirmidhi assured him that he knew the traditions by heart. The traditionist was not convinced of his genuineness, even though Imam Tirmidhi recited the traditions to him, so Imam Tirmidhi asked him to recite some other traditions. The traditionist recited forty traditions which Imam Tirmidhi repeated without making a single error, thus showing his remarkable power of committing traditions to memory.
Moulana Rashid Ahmad Gangohi (d.1323 A.H.), a commentator on the Jami' said that Imam Tirmidhi was born blind. This opinion is erroneous since al-Dhahabi (d.748 A.9) and the majority of the scholars agree that his blindness occurred during the latter portion of his life and he remained blind for two years. Hence he was commonly referred to as al-Darir (blind). His blindness is usually attributed to his weeping over Imam Bukhari's death (d.256 A.H.) or his excessive weeping for the fear of Allah.