Zayd bin Thabit (may Allah be pleased with him) was the most knowledgeable in the laws of inheritance and learned the Syriac language

It is narrated from Sayyiduna Zayd bin Thabit (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) asked me: "Do you know the Syriac language?" I said: No. So he (peace and blessings be upon him) said: "Learn it, for many letters come to us." So I learned it in just seventeen days. Al-A'mash says: Letters used to come to him (peace and blessings be upon him) which he liked to show only to someone in whom he had complete trust.
This hadith is sahih (authentic) provided that Thabit bin Ubayd heard it from Sayyiduna Zayd bin Thabit (may Allah be pleased with him), and the two Shaykhs did not record it.

It is narrated from Sayyiduna Uqbah bin al-Fakih (may Allah be pleased with him) that he said: I said to Sayyiduna Zayd bin Thabit (may Allah be pleased with him): "O Abu Kharijah!"

It is narrated from Sa'id bin al-Musayyib (may Allah have mercy on him) that he said: I attended the funeral of Sayyiduna Zayd bin Thabit (may Allah be pleased with him); then, when he was buried in his grave (he mentioned the hadith).

It is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "The most merciful of my Ummah towards my Ummah is Abu Bakr; the sternest of them in the matter of Allah is Umar; the most truthful of them in modesty is Uthman; the foremost reciter of the Book of Allah is Ubayy bin Ka'b; the most expert of them in the knowledge of inheritance (fara'id) is Zayd bin Thabit; and the most knowledgeable of them about the lawful and the unlawful is Mu'adh bin Jabal. Know that every nation has a trustee (amin), and the trustee of this nation is Abu Ubaydah bin al-Jarrah."
This chain is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it with this wording; they agreed, with this chain of theirs, only on the mention of Abu Ubaydah (may Allah be pleased with him), and I have explained its reason in my book "al-Talkhis".

It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that he took hold of the stirrup of the mount of Sayyiduna Zayd bin Thabit (may Allah be pleased with him), so Zayd (may Allah be pleased with him) said: "O cousin of the Messenger of Allah (peace and blessings be upon him)! Step aside," to which Ibn Abbas (may Allah be pleased with them both) replied: "This is how we treat (with respect) our elders and our scholars."
This hadith is sahih (authentic) on the condition of Imam Muslim, but the two Shaykhs did not record it. (Imam al-Hakim says:) Regarding the virtues of Zayd bin Thabit (may Allah be pleased with him), my intention was to begin with the hadith about the compilation of the Qur'an, since it contains many of his merits; but since the two Shaykhs agreed on recording it, I have left it out.