What is your opinion of those who criticise al-Haafiz Ibn Hajar?
Question

                What is your opinion of those who criticise al-Haafiz Ibn Hajar?.
Praise be to Allah.
    al-Haafiz Ibn Hajar (may Allah have mercy on him) and other 
    scholars are not infallible or free of error. Not one of them is infallible. 
    I wrote some comments on his book al-Fath al-Baari, from the beginning of it 
    to Kitaab al-Hajj, and I noted my reservations about some points (may Allah 
    have mercy on him). 

    The point is that he is not infallible, and scholars who were 
    greater than him were not infallible either. When the truth becomes 
    apparent, then truth is the lost property of the believer. If proof is 
    established concerning some matter, then we must follow that for which proof 
    has been established from the Book of Allah or the Sunnah of His Messenger 
    (blessings and peace of Allah be upon him), even if it goes against the view 
    of a great imam, an imam greater than al-Haafiz Ibn Hajar, and even if it 
    goes against the view of some of the Sahaabah. Allah says (interpretation of 
    the meaning):

    “(And) if you differ in anything amongst yourselves, refer 
    it to Allaah and His Messenger (صلى 
    الله عليه وسلم)…”

    [al-Nisa’ 4:59]

    He did not say: refer to so-and-so or so-and-so, rather He 
    said “refer it to Allaah and His Messenger (صلى 
    الله عليه وسلم), if you believe in Allaah and 
    in the Last Day. That is better and more suitable for final determination.” 
    And He said (interpretation of the meaning):

    “And in whatsoever you differ, the decision thereof is 
    with Allaah (He is the ruling Judge)”

    [al-Shoora 42:10]. 

    But it is essential to be certain of the issue and show 
    respect the scholars and observe proper etiquette with them. If a person 
    finds a weak view on the part of one of the imams or scholars or respected 
    muhadditheen, then that does not detract from their status, and he must 
    respect the scholars, observe proper etiquette with them, speak good words 
    and not revile them or scorn them. Rather he should explain the truth with 
    evidence, whilst also praying for the scholar, seeking Allah's mercy for him 
    and asking Allah to pardon him. 

    This is how the attitude of people of knowledge should be 
    towards other people of knowledge: they should appreciate the people of 
    knowledge, and acknowledge their status, position and virtue. 

    But that should not prevent them from pointing out mistakes, 
    if they find an obvious mistake, whether on the part of a classical scholar 
    or a modern one. The scholars are still debating with one another until 
    today, and will continue to do so until the Day of Resurrection. Imam Maalik 
    (may Allah have mercy on him) said: There is no one among us but he may 
    refute or be refuted, except the occupant of this grave -- meaning the 
    Messenger of Allah (blessings and peace of Allah be upon him). 

    Imam al-Shaafa’i (may Allah have mercy on him) said: The 
    scholars are agreed that the one to whom the Sunnah of the Messenger of 
    Allah (blessings and peace of Allah be upon him) has become clear has no 
    right to forsake it in favour of the view of any person. 

    Imam Ahmad (may Allah have mercy on him) said: I am amazed at 
    people who know the isnaad and its soundness -- meaning from the Prophet 
    (blessings and peace of Allah be upon him) -- but they follow the view of 
    Sufyaan -- meaning al-Thawri. Sufyaan (may Allah have mercy on him) was a 
    great imam, yet despite that, Ahmad criticised the one who ignores the 
    hadeeth and follows his opinion. Then Imam Ahmad (may Allah have mercy on 
    him) recited the verse (interpretation of the meaning): 
    “And let those who oppose the Messenger’s (Muhammad 
    صلى الله عليه وسلم) 
    commandment (i.e., his Sunnah – legal ways, orders, acts of worship, 
    statement, etc.) (among the sects) beware lest some Fitnah (disbelief, 
    trials, afflictions, earthquakes, killing, overpowered by a tyrant, etc.) 
    befall them or a painful torment be inflicted on them” [al-Noor 24:63]. 

    Imam Abu Haneefah (may Allah have mercy on him) said: If 
    there comes a hadeeth from the Messenger of Allah (blessings and peace of 
    Allah be upon him), then we accept and follow willingly, and if there comes 
    a report from the Companions (may Allah be pleased with them), then we 
    accept and follow willingly, but if there comes a report from the Taabi’een, 
    then we are men and they are men (i.e., we are on an equal footing with 
    them). 

    And the scholars said a great deal concerning this matter. 
    And Allah is the source of strength. End quote.