1868 - Issue: He said: "And he shall not overturn the judgment of another when it is raised to him, except for that which contradicts an explicit text of the Book [Quran], or the Sunnah, or a consensus (ijma')."

The summary of this is that if a case is brought to a judge upon which another judge has already ruled, and it becomes clear to him that the [previous] judge erred, or it becomes clear to him that he himself erred, you must consider: if the error was due to contradicting an explicit text of the Book, the Sunnah, or a consensus, he shall overturn the judgment. Al-Shafi'i held this view, adding: if it contradicts an evident analogy (qiyas), he shall overturn it. From Malik and Abu Hanifah, it is narrated that they both said: He shall not overturn a judgment unless it contradicts a consensus. Then, they contradicted this; for Malik said: If he rules by preemption (shuf'ah) for the neighbor, he shall overturn his judgment. Abu Hanifah said: If he rules for a sale where the naming [of the price] was omitted, or he judges between slaves by drawing lots, he shall overturn his judgment. Muhammad ibn al-Hasan said: If he rules by a witness and an oath, he shall overturn his judgment. These are issues of disagreement that are consistent with the Sunnah. They argued that he does not overturn it as long as it does not contradict a consensus, because disagreement is permissible therein, so he does not overturn the judgment, just as there is no [explicit] text regarding it. It was narrated from Abu Thawr and Dawud that he shall overturn everything that becomes clear to him as an error; because 'Umar, may Allah be pleased with him, wrote to Abu Musa: "Let not a judgment you passed yesterday, and then reviewed your own opinion on it today and were guided to the right way, prevent you from returning to the truth; for returning to the truth is better than persisting in falsehood." And because it is an error, it is mandatory to retract it, just as if it had contradicted a consensus. It was narrated from Malik that he agreed with them regarding his own [prior] judgment. Our argument, for overturning it if it contradicts a text or consensus, is that it is a judgment that did not meet its condition, so it must be overturned, just as if it did not contradict a consensus. The proof of its contradiction of the condition is that the condition for a judgment by ijtihad is the absence of a text, evidenced by the report of Mu'adh, and because if he abandons the Book and the Sunnah, he has been negligent, so his judgment must be overturned, just as...