To what extent is the narration sound regarding the tradition related about Umar ibn al-Khattab, may Allah be pleased with him, when he recited: "And fruits and 'abbā" [Qur'an 80:31], then said: "We have recognized this fruit, but what is the 'abbā?" Then he returned to himself, saying: "Indeed, this is an act of presumption, O Umar!"?

The narration from Umar, may Allah be pleased with him, is authentic. It was narrated from him by Anas ibn Malik, may Allah be pleased with him, through several chains of transmission from Anas. Its wording is: Umar recited (the Surah (definition)) "He frowned and turned away" (Abasa) until he reached "and fruits and grass" (wa fakihataw wa abba). He then said: "We already know what fruits are, but what is abb (grass)?" Then he said: "Verily, this is an unnecessary burden (takalluf)." In other narrations: "What we already know is sufficient for us," or "Follow what is clear to you in this Book, and what is clear, adhere to it, and what is not, leave it," or "By Allah, this is an unnecessary burden (takalluf), so take, O people, what has been made clear to you from it; what you know, act upon it, and what you do not know, entrust its knowledge to Allah, the Exalted." This narration was authenticated by Al-Jawzaqani and Ibn Kathir.