وَعَن الْحسن قَالَ: «الْعِلْمُ عِلْمَانِ فَعِلْمٌ فِي الْقَلْبِ فَذَاكَ الْعلم النافع وَعلم على اللِّسَان فَذَاك حُجَّةُ اللَّهِ عَزَّ وَجَلَّ عَلَى ابْنِ آدَمَ» . رَوَاهُ الدَّارمِيّ

Al-Hasan said that knowledge is of two kinds

knowledge in theheart, which is the beneficial type; and knowledge on the tongue, whichis God’s allegation against a human being.” Darimi transmitted it.