"How do you find me?" He said: "I find you a horn." He said: Then he raised the whip against him and said: "A horn of what?" He said: "A horn of iron, a trustworthy and severe one." He said: "How do you find the one who will come after me?" He said: "I find him a righteous caliph, except that he will favor his relatives." Umar said: "May Allah have mercy on Uthman" — three times. He said: "How do you find the one after him?" He said: "I find him the rust of iron." So Umar placed his hand on his head and said: "O foulness, O foulness!" He said: "O Commander of the Faithful, he is a righteous caliph, but he will be made caliph at a time when the sword is drawn and blood is being shed."

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(1) Added in one version alone: "a horn of iron." Its meaning: a fortress of iron.
(2) Its chain of transmission is weak. Al-Aqra', the mu'adhdhin of Umar ibn al-Khattab — even though al-'Ijli declared him trustworthy and Ibn Hibban mentioned him — al-Dhahabi said about him in "Al-Mizan": "He is not known." A single shaykh alone narrated from him. We say: So he is unknown, and moreover, there is severe oddity in its text.
It was also transmitted by Abu 'Ubayd al-Qasim ibn Sallam in "Gharib al-Hadith" 3/235, and Ibn 'Asakir in "Tarikh Dimashq" 39/189 via the path of Yazid ibn Harun, from Sa'id ibn Iyas al-Jurayri, from him. The narration of Abu 'Ubayd is abridged.
It was also transmitted by Ibn Abi Shaybah 12/30-31 and 15/214, and from him Ibn Abi 'Asim in "Al-Ahad wa al-Mathani" (107) from Abu Usamah Hammad ibn Usamah, from Kahmas ibn al-Hasan, from 'Abdullah ibn Shaqiq, from him.
Al-Khattabi said: "Al-Sada' (rust) is what covers iron of filth and accumulates upon it of dirt. And his saying: 'Ya dafrahu, ya dafrahu' — for al-dafar (with an unpointed dal and a sukun on the fa') is stench, and from it the world is called 'Umm Dafar.' As for al-dhafar (with a pointed dhal and a fatha on the fa'), it is said of any sharp, strong smell, whether pleasant or foul."
Note: This report we have established from (A), (B), (D), and (E), and it is in the narration of Ibn al-'Abd and Ibn Dasah. Al-Mizzi mentioned it in "Al-Tuhfah" (10458) and said: "Abu al-Qasim did not mention it, and it is in the narration." We say: meaning in the narration of Al-Lu'lu'i. Thus said Al-Mu'ayy, even though the report did not appear in most =