وَعَن الْحسن
قَالَ: «الْعِلْمُ عِلْمَانِ فَعِلْمٌ فِي الْقَلْبِ فَذَاكَ الْعلم النافع وَعلم على اللِّسَان فَذَاك حُجَّةُ اللَّهِ عَزَّ وَجَلَّ عَلَى ابْنِ آدَمَ»
knowledge in the heart, which is the beneficial type; and knowledge on the tongue, which is God’s allegation against a human being.
Mishkat al-Masabih 255, Book 3, Knowledge, Hadith 66. 1 min read