Imam Ibn Kathir said about Shaykh al-Islam Ibn Taymiyyah :
“The least he would do when he heard something was to memorise it and then busy himself with learning it. He was intelligent and had much committed to memory, and he became an Imam in tafsir and everything linked to it and knowledgeable in fiqh. Indeed it was said he was more knowledgeable of the fiqh of the madhahib then the followers of those very same madhahib in his time and other than his time. He was a scholar in Usul and the branches of the religion and grammar and the language and other textual and intellectual sciences . No scholar of a science would speak to him except that he thought that that science was the speciality of Ibn Taymiyyah. As for hadith then he was the carrier of its flag, a hafidh and able to distinguish the weak from the strong, fully acquainted with the narrators.”
ولازم الشماع بنفسه مدة سنين ، ثم اشتغل بالعلوم ، وكان ذكيا كثير المحفوظ ، فصار إماما في التفسير وما يتعلق به ، عارفا بالفقه واختلاف العلماء ، والأضلين والنحو واللغة ، وغير ذلك من العلوم التقلية والعقلية ، وما تكلم معه فاضل في فن من الفنون العلمية إلا ظن أن ذلك الفن فنه ، ورآه عارفا به متقنا له ، وأما الحديث فكان حافظا له مثنا وإسنادا ، مميزا بين صحيحه وشقيمه ، عارفا برجاله متضلعا ا من ذلك
(Al-Bidayah Wa al-Nihayah 18/298)
