Grading: (3) This hadith is "batil" (false), and this chain is extremely weak (wahin bi-marrah).
Narrator research: The majority declared Abu al-Salt Abd al-Salam bin Salih weak; indeed some accused him of lying. Al-Uqayli, al-Nasa'i and al-Daraqutni said: "He was a vile Rafidi." The author (al-Hakim) himself said in "al-Madkhal ila al-Sahih" (139): "He narrated munkar hadiths from Abu Mu'awiyah and others."
Clarification: We say: no one thought well of him except Yahya bin Ma'in. Al-Dhahabi sought an excuse for Yahya in "al-Siyar" (11/447), saying: "Hearts are disposed to love whoever treats them well, and this man was kind to Yahya. We always listen to Yahya and take his word as proof regarding narrators, so long as it has not become clear to us that a man whom he alone strengthened is weak, or that a man whom he weakened is strong." We say: this hadith was known only through this Abu al-Salt, and whoever else narrated it stole it from him; Ibn Adi mentioned this in several places in his book "al-Kamil" (1/189, 2/341, 3/412, 5/617 and 177).
Reference / Source: Ibn Hibban said in "al-Majruhin" (2/152): "This is something without any basis; it is not from the hadith of Ibn Abbas, nor Mujahid, nor al-A'mash, nor did Abu Mu'awiyah narrate it. Whoever narrates this text has stolen it from this Abu al-Salt." Al-Daraqutni said in his "Ta'liqat 'ala al-Majruhin" (page 179): "It is said that Abu al-Salt fabricated it upon Abu Mu'awiyah, and a group stole it from him and narrated it from Abu Mu'awiyah." Ibn al-Jawzi said something similar in "al-Mawdu'at" (2/118). And in Ibn Qudamah's "al-Muntakhab min Ilal al-Khallal" (120): Imam Ahmad was asked about this hadith and said: "May Allah disgrace Abu al-Salt." And in the narration of al-Marrudhi from him, as in "al-Ilal wa Ma'rifat al-Rijal" (308), he said: "We have never heard of this." We say: Imam Ahmad is among the best known of those who narrated from Abu Mu'awiyah - he narrated hundreds of hadiths from him - and he denies that this is from his hadith.
Scholarly point: Abu Bakr bin al-Arabi said in "Ahkam al-Qur'an" (3/86): It is a false hadith; the Prophet (peace and blessings be upon him) is a city of knowledge and its gates are his Companions - among them the wide gate and among them the middling one, according to their ranks in knowledge. Shaykh al-Islam Ibn Taymiyyah said in "Minhaj al-Sunnah" (7/515): "It is counted among the fabrications, even though al-Tirmidhi narrated it; Ibn al-Jawzi mentioned it and showed that all its routes are fabricated. Its falsehood is known from its very text: if the Prophet (peace and blessings be upon him) were the city of knowledge and it had only one gate, and only one person conveyed knowledge from him, the affair of Islam would be corrupted. For this reason the Muslims agree that it is not permissible for the one who conveys knowledge from him to be a single person; rather those who convey it must be a mass (tawatur) through whose report knowledge is attained by the one who was absent."

Grading: Al-Dhahabi in "Talkhis al-Mustadrak", objecting to al-Hakim's declaring the hadith sahih and his declaring Abu al-Salt trustworthy, said: "Rather it is mawdu' (fabricated), and Abu al-Salt - no, by Allah - is neither thiqah nor reliable (ma'mun)."

Technical note / Defect ('illah): We say: there is another defect in it, namely the 'an'anah of al-A'mash from Mujahid. Ya'qub bin Shaybah mentioned in his "Musnad" (as in "Ikmal Tahdhib al-Kamal" 6/92) that he asked Ali bin al-Madini: How much did al-A'mash hear from Mujahid? He said: Nothing of it is established except where he said "I heard", which is about ten; his hadiths from Mujahid are really through Abu Yahya al-Qattat, Hakim bin Jubayr and the like. We say: these two are weak and munkar in hadith; Hakim is the weaker of the two and closer to being abandoned, and al-Juzajani accused him of lying.
Reference / Source: Allamah Abd al-Rahman al-Mu'allimi al-Yamani discussed the weakness of this hadith excellently in his notes on al-Shawkani's "al-Fawa'id al-Majmu'ah" (pages 349-353).

Grading (other views): Despite all this, al-Ala'i called it "hasan" in "al-Naqd al-Sahih" (18), and Ibn Hajar called it hasan in one of his fatwas (as al-Suyuti reported in "al-La'ali' al-Masnu'ah" 1/306)! And al-Tabari declared it "sahih" in "Tahdhib al-Athar" (page 104) from the hadith of Ali!

Reference / Source: Ibn Ma'in narrated it in "Ma'rifat al-Rijal" (1788), al-Tabari in "Tahdhib al-Athar" (page 105), al-Tabarani in "al-Kabir" (11061), Ibn Adi in "al-Kamil" (5/67), al-Khatib in "Tarikh Baghdad" (12/318), Ibn al-Maghazili in "Manaqib Ali" (121, 123, 124), Ibn Asakir in "Tarikh Dimashq" (42/380), Ibn al-Jawzi in "al-Mawdu'at" (661) and Ibn al-Athir in "Usd al-Ghabah" (3/596-597), through various routes from Abu al-Salt Abd al-Salam bin Salih, with this same chain.

Important point: This narration will come with the author through the route of al-Husayn bin Fahm from Abu al-Salt at number (4701 M).

Reference / Source: Al-Tabari narrated it in "Tahdhib al-Athar" (page 105) from Ibrahim bin Musa al-Razi, and said: "This (Ibrahim) is not al-Farra'."

Reference / Source: Abu Zur'ah al-Razi in "Su'alat al-Bardha'i" (414), al-Uqayli in "al-Du'afa'" (1100), al-Khatib in "Tarikh Baghdad" (13/39-40), Ibn Asakir (42/380) and Ibn al-Jawzi (659) through the route of Umar bin Isma'il bin Mujalid; and Ibn Hibban in "al-Majruhin" (1/130), and through his route Ibn al-Jawzi (665), via Isma'il bin Muhammad bin Yusuf, from Abu Ubayd al-Qasim bin Sallam.

Reference / Source: And Ibn Adi (1/189), and through his route Hamzah bin Yusuf al-Sahmi in "Tarikh Jurjan" (page 65), Ibn Asakir (12/379) and Ibn al-Jawzi (662), through the route of Ahmad bin Salamah Abu Amr al-Jurjani.

Reference / Source: And Khaythamah bin Sulayman (as in "Mizan al-I'tidal" 3/444) through the route of Mahfuz bin Bahr al-Antaki, from Musa bin Muhammad al-Ansari al-Kufi.

Reference / Source: And Ibn Adi (2/341 and 5/67), and through his route Ibn Asakir (42/379) and Ibn al-Jawzi (664), from al-Hasan bin Ali bin Salih al-Adawi, from al-Hasan bin Ali bin Rashid.

Reference / Source: Al-Khatib al-Baghdadi in "Tarikh Baghdad" (571-572), and through his route Ibn Asakir (42/379) and Ibn al-Jawzi (658), through the route of Abdullah bin Muhammad bin Abdullah al-Shahid (known as Ibn al-Thallaj), from Abu Bakr Ahmad bin Fadhawayh bin Azrah al-Tahhan, from Abu Abdullah Ahmad bin Muhammad bin Yazid bin Salim, from Raja' bin Salamah.

Reference / Source: And al-Khatib (8/55), and through his route Ibn Asakir (42/381) and Ibn al-Jawzi (657), through the route of Ja'far bin Muhammad Abi Muhammad al-Baghdadi.
Important point: All eight of these narrators narrate it from Abu Mu'awiyah Muhammad bin Khazim al-Darir with this same chain.

Technical note / Defect ('illah): All these routes are criticised. Ibn al-Jawzi discussed each of them individually, except the routes of Ibrahim bin Musa al-Razi and Musa bin Muhammad al-Ansari.
Narrator research: As for Ibrahim bin Musa al-Razi - about whom al-Tabari stated with certainty that he is not "al-Farra'" - he is "majhul" and is not known anywhere except in this report. As for Musa bin Muhammad al-Ansari, he is "thiqah", but the narrator from him, Mahfuz bin Bahr, was declared a "liar" by Abu Arubah al-Harrani.

Reference / Source: Ibn al-Jawzi mentioned in "al-Mawdu'at" (2/115) another "corroboration" in Abu Bakr bin Marduwayh through the route of al-Hasan bin Uthman, from Mahmud bin Khidash, from Abu Mu'awiyah.
Narrator research: Mahmud bin Khidash is "thiqah", but the one narrating from him, al-Hasan bin Uthman (who is al-Tustari), was declared a "liar" by Ibn Adi.

Note / Clarification: The route of Muhammad bin Ja'far al-Faydi from Abu Mu'awiyah will come in the next hadith; see the discussion of it there.

Reference / Source: Ibn Adi (3/412), and through his route Ibn Asakir (42/379) and Ibn al-Jawzi (663), narrated it through the route of Abu al-Fath Sa'id bin Uqbah al-Kufi; and al-Ajurri in "al-Shari'ah" (1551) and Ibn Adi (5/177) through the route of Uthman bin Abdullah bin Amr bin Uthman bin Affan, from Isa bin Yunus al-Sabi'i. Both of them (Sa'id and Isa) brought it from Sulayman al-A'mash with this same chain.
Technical note / Defect ('illah): About Sa'id bin Uqbah, Ibn Adi said: "He is unknown, not trustworthy." Isa bin Yunus is "thiqah", but the one narrating from him (Uthman) is "da'if" and a narrator of munkar reports; indeed al-Daraqutni declared him "matruk al-hadith".

Important point: On this topic there is the narration of Jabir bin Abdullah (may Allah be pleased with him), which will come with the author at number (4689), and its chain is "ruinous" (talif).

Reference / Source: This narration from Ali (may Allah be pleased with him) himself is recorded by al-Tirmidhi (3723), Ibn Jarir al-Tabari in "Tahdhib al-Athar" (Musnad Ali: page 104), Ibn Hibban in "al-Majruhin" (2/94) and Ibn al-Jawzi in "al-Mawdu'at" (654-656).
Grading: Al-Tirmidhi rejected it and said: "The hadith is gharib and munkar." He asked al-Bukhari about it in "al-Ilal al-Kabir" (699), and he did not recognise it. Al-Tabari, however, declared its chain sahih!
Technical note / Defect ('illah): Al-Daraqutni in "al-Ilal" (386) mentioned a disagreement over its chain upon Sharik al-Nakha'i, then said: "The hadith is inconsistent (mudtarib) and not established." We say: Ibn al-Jawzi also exposed the flaws of the routes of Ali's hadith.

Narrator research: (1) This is what Ibn Ma'in said (i.e. he declared him trustworthy), although he had a degree of "leniency" in declaring narrators trustworthy. Ibn Hibban also mentioned him in "al-Thiqat", but no declaration of his trustworthiness is reported from anyone other than these two. Abu al-Walid al-Baji mentioned him in "al-Ta'dil wa al-Tajrih" (2/624) and said: "He seems to be unknown." Ibn Hajar said in "Tahdhib al-Tahdhib": "He has hadiths in which he was contradicted." Al-Mu'allimi al-Yamani said in his notes on "al-Fawa'id al-Majmu'ah" (350): "Ibn Ma'in counted Muhammad bin Ja'far al-Faydi as a corroborator, while others counted him as a thief (of hadith), and nothing satisfactory has become clear about al-Faydi's condition." As for the discussion of Abu al-Salt, it has passed in the previous hadith.