Within the book Kitāb aṣ-Ṣafadīyyah of Shaykh al-Islām ibn Taymīyyah رَحِمَهُ ٱللَّٰهُ (d. 728 AH /1328 CE), he speaks on the matter of using Ṣaḥīḥ Aḥādīth as a proof, & the importance of doing so.
Shaykh al-Islām ibn Taymīyyah رَحِمَهُ ٱللَّٰهُ states: “Many of those who claim to follow the Sunnah and write books about it do not know anything about Ḥadīth or understand it. Rather you may find a man who is prominent among them writing a book in which he quotes reports about the divine attributes or refuting misinterpretations of the divine attributes, in which he quotes Ḍaʻīf Aḥādīth alongside Ṣaḥīḥ ones which are widely accepted by the scholars, and he regards them all as equal and does not differentiate between them.
I have seen more than one of those who write about the Sunnah according to the way of Ahl al-Ḥadīth, such as the followers of Imām Mālik, Imām Aḥmad, Imām ash-Shāfiʿī, & others among the Sufīyyah and scholars of Kalām, quoting to support their arguments about matters of Uṣūl ad-Dīn Aḥādīth that are not fit to be relied on in the context of encouraging righteous deeds, let alone in the context of Fiqhī issues, (and) let alone in the context of Uṣūl ad-Dīn.
The A’Immah would narrate concerning a particular issue what they knew of Aḥādīth that are not known to be false, but were Marfū’, Musnad, or Mawqūf, and statements of the Ṣaḥābah & Tabi’īn, because those reports strengthen one another. For example, when discussing some fundamental matter of Islām, in the context of examining the different views of the four A’Immah & the Salaf, there are reports and opinions that may be mentioned as the basis of an argument, and other things may be mentioned to lend extra strength to the argument.”
May Allāh have mercy upon ibn Taymīyyah & grant him the highest ranks of Jannah for his efforts & contributions to the religion of Islām.
All praise is due to Allāh, may His peace & blessings be upon our final Prophet Muḥammad, his family, his companions, & all those who follow him in guidance.
Kitāb aṣ-Ṣafadīyyah (كتاب الصفدية) by Shaykh al-Islām ibn Taymīyyah | Volume 1, Pages 286-287
Ṣafīullāh Labīb ibn Salīm ʿAbd al-Malik
21st of Jumādā al-ʾŪlā 1443 – 25th of December 2021