Musannaf Ibn Abi Shaybah 31905 — Reports on reciting the Quran

Umar bin Zayd said that Sayyiduna Umar (may Allah be pleased with him) wrote a letter to Sayyiduna Abu Musa al-Ash'ari (may Allah be pleased with him) and said: "After praise and salutations: acquire understanding of the Sunnah, acquire understanding of the Arabic language, and recite the Qur'an making its vowel endings (i'rab) clear, for it is in the Arabic language; and trace your lineage to the tribe of Ma'add, for you are of the tribe of Ma'add."