Ash Shaykh Saalih As Suhaymee said:
And knowledge is the greatest provision which the Muslim takes as a provision and that is because with knowledge Islaam is known from Disbelief, guidance is known from misguidance, Tawheed from Shirk, the Sunnah from innovation, Truth from falsehood, the knowledge which its companion acts with is like a scale which the things are weighed with, so the matters are weighed with it and he doesn’t place his foot except where its befitting that it be placed, so knowledge is a light which illuminates for him the path as Imam Maalik said ‘Knowledge is not by many narration, rather knowledge is a light which Allah aza wa jal places in the hearts’
And as Ash shaafiee said 
I complained to Wakee about my bad memory 
So he directed me to leaving off sins 
And said know that the knowledge is light 
And the light of Allah is not given to a sinner 
Explanation of An Nuniyah al Qahtaaniyah called Al Qutoof Ad Dawaani
Pg 83
Majid Jawed Al Afghanee