The Messenger of Allah ﷺ ordered me to learn for him certain words from the writing of the Jews. He said, "By Allah, I do not trust the Jews with my correspondence."Zayd said, Not even half a month passed before I had learned it for him. Once I had mastered it, whenever he wrote to the Jews, I would write to them on his behalf, and whenever they wrote to him, I would read their letters to him.
حدثنا علي بن حجر أخبرنا عبد الرحمن بن أبي الزناد عن أبيه عن خارجة بن زيد بن ثابت
أمرني رسول الله ﷺ أن أتعلم له كلمات من كتاب يهود قال إني والله ما آمن يهود على كتابي قال فما مر بي نصف شهر حتى تعلمته له قال فلما تعلمته كان إذا كتب إلى يهود كتبت إليهم وإذا كتبوا إليه قرأت له كتابهم
[Its isnad is hasan]. Abu Dawud narrated it in the Book of Knowledge, chapter on narrating hadith of the People of the Book, hadith no. 3645, from the narration of Abdul-Rahman bin Abu Zinad through the same chain, and Bukhari mentioned it with a suspended chain, hadith no. 7195.