"I entered upon the Messenger of Allah (ﷺ) while there was a scribe in front of him, and I heard him saying: 'Put the pen on your ear, for that is more conducive to the scribe remembering.'"
Jami` at-Tirmidhi Book 42, Hadith 27
← Previous Hadith that the Messenger of Allah (ﷺ) said: "When one of you writes something, then let him Yutarrib (smeared with dust to dry the ink) it, for that is more conducive to the need."

Jami` at-Tirmidhi Book 42, Hadith 26 Next Hadith → "The Messenger of Allah (ﷺ) ordered me to learn some statements from writings of the Jews for him, and he said: 'For indeed by Allah! I do no trust the Jews with my letters.'" He said: "Half a month did not pass before I learned it, when he (ﷺ) wanted to write to the Jews I would write it to them, and when they wrote to him I would read their letters to him."

Jami` at-Tirmidhi Book 42, Hadith 28