يَا كُمَيْلَ بْنَ زِيَادٍ مَعْرِفَةُ الْعِلْمِ دِينٌ يُدَانُ بِهِ بِهِ يَكْسِبُ الْإِنْسَانُ الطَّاعَةَ فِى حَيَاتِهِ وَجَمِيلَ الْأُحْدُوثَةِ بَعْدَ وَفَاتِهِ وَ الْعِلْمُ حَاكِمٌ وَالْمَالُ مَحْكُومٌ عَلَيْهِ.
O Kumayl, knowledge is belief which is acted upon. With it man acquires obedience during his life and a good name after his death. Knowledge is the ruler while wealth is ruled upon.