Al-Muzani, the disciple of Imam al-Shafi‘i, said:

“The Companions of the Messenger of Allah ﷺ disagreed: some of them declared others mistaken, and some examined and challenged one another’s statements. Had they believed every opinion to be correct, they would not have done so.

‘Umar ibn al-Khattab became angry over the dispute between Ubayy ibn Ka‘b and Ibn Mas‘ud about praying in a single garment. Ubayy said, ‘Performing the prayer in one garment is fine and praiseworthy,’ whereas Ibn Mas‘ud said, ‘That was only when clothing was scarce.’ ‘Umar went out in a rage and said, ‘Two men from the Companions of the Messenger of Allah ﷺ—whom people look to and take knowledge from—have differed! Ubayy has spoken the truth, and Ibn Mas‘ud has not fallen short, yet I swear I will not hear anyone differ about this after my standing here today without dealing with him in such-and-such a way.’” (1)

Al-Muzani also said:

“It is said to the one who allows disagreement and claims that if two scholars exercise ijtihād concerning an issue—one declaring it lawful and the other unlawful—each of them, through his ijtihād, attains the truth: ‘Is this assertion based on a textual foundation or on analogy?’

If he says, ‘On a textual foundation,’ he is told, ‘How can it be a foundation when the Book itself negates disagreement?’ And if he says, ‘On analogy,’ he is told, ‘How can the foundational texts negate disagreement while you permit yourself to derive by analogy the permissibility of disagreement?’ No rational person—let alone a scholar—would countenance such a view.” (2)

Should someone object, “What you have cited from Imam Mālik—that the truth is single and admits no multiplicity—appears to contradict