بسم الله الرحمن الرحيم
Imām al-Shawkānī said: “What has been explicitly declared authentic (Sahīh) or good (Hasan) is permissible to be acted upon, and what has been explicitly declared weak is not permitted to be acted upon.” (Nayl al-Awtār 1/15)
Imām Al-Shawkānī also said: “The legal (Sharī’ah) rulings are equal in footing, there is no difference between them, so it is not lawful to establish anything from them (i.e. legal rulings) except by what establishes evidence, otherwise it would be speaking about Allāh regarding what He did not say, and in it is the punishment that is well-known” (al-Fawā’id al-Majmū’ah fī al-Ahādīth al-Mawdū’ah p. 283)
Shaykh Siddīq Hasan Khān al-Qanūjī said: “The correct [position] that there is no escape from – is that legal rulings are equal in footing, so one should not act upon a hadīth until it is [established to be] authentic (Sahīh) or good (hasan) in itself (li-dhātihī) or due to external factors (li-ghayrihī), or its weakness is remedied so it rises to the level of good (hasan) in itself (li-dhātihī) or due to external factors (li-ghayrihī).” (Nuzul al-Abrār pp. 7-8)
Shaykh Salīm Al-Hilālī said: “Using weak hadīth as evidence – whether in beliefs (‘aqā’id), or [legal] rulings (ahkām), or encouragement and warning (targhīb wa tarhīb) – after the principles of the sciences of hadīth have been established – is not permitted absolutely, because in using it as evidence is establishing worship (‘ibādah) with what Allāh did not legislate.” (al-Mutqin Sharh Tadhkirah of Ibn Mulaqqin pg. 61)
Jalāl al-Dīn al-Dawānī said: “They agreed that weak hadīth do not establish legal rulings (al-ahkām ash-shar’iyyah).
Then they mentioned that it is permissible, rather recommended, to act upon weak hadīth in virtues of actions. Among those who explicitly stated this is al-Nawawī in his books, especially the book ‘al-Adhkār’.
There is a problem in this, because the permissibility of action and its recommendation are both among the five legal rulings [i.e. obligation, recommendation, permission, dislike, prohibition].
So when action according to weak hadīth becomes recommended, its establishment is by weak hadīth, and that contradicts what has been established regarding the non-establishment of rulings by weak hadīth.” (Unmūdhaj al-‘Ulūm pg. 2)
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