Majma al-Zawaid — Hadith 7137

Abu al-Zinad says that he obtained this letter from Kharijah, the son of Sayyiduna Zayd bin Thabit (may Allah be pleased with him): "Seeking blessing through the name of Allah Almighty, the Most Gracious, the Most Merciful. This is from Zayd bin Thabit to the servant of Allah and Commander of the Faithful, Sayyiduna Mu'awiyah. Peace be upon you, O Commander of the Faithful, and may the mercy of Allah Almighty descend upon you. I praise before you Allah, besides whom there is no god. To proceed: You have asked me about the inheritance of the grandfather, the brothers and kalalah, and about many other matters on which rulings are given and whose details are not known. After the Prophet (peace and blessings be upon him), we were present at such matters in the presence of the caliphs, and from them we retained what we wished to retain. Now, after that, whoever asks us for a ruling concerning inheritance, we give him a fatwa accordingly."
Al-Tabarani recorded it as "wijadah" (from a found written source); its chain contains a narrator, Abd al-Rahman bin Abi al-Zinad, whom al-Nasa'i (may Allah have mercy on him) and others declared thiqah (trustworthy), while the majority declared him da'if (weak).