It is narrated from Imam Hasan al-Basri, may Allah have mercy on him, that knowledge is of two types: the knowledge that settles in the heart, this is beneficial knowledge; the other knowledge (which remains) only on the tongue, then this knowledge is an argument from Allah against the son of Adam.
Hadith Referenceسنن دارمي / مقدمه / 375
Hadith Gradingتحقیق (حسین سلیم أسد الدارانی):إسناده صحيح إلى الحسن وهو موقوف عليه، [مكتبه الشامله نمبر: 376]
Hadith Takhrijیہ اثر امام حسن بصری رحمہ اللہ پر موقوف ہے، اور ان تک سند صحیح ہے۔ مزید دیکھئے: [المصنف 235/13] ، [تاريخ بغداد 346/4] ، [العلل المتناهية 88]
Brief Explanation
(Commentary on Ahadith 371 to 375) That is, knowledge which remains confined only to the tongue and does not settle in the heart will remain incapable of action and will not be of any benefit; therefore, along with knowledge, there must also be action.