Abu Dawud Book 19, Hadith Number 3634.
Narated By Abu al-Darda’ : Kathir ibn Qays said: I was sitting with Abu al-Darda’ in the mosque of Damascus.
A man came to him and said: AbudDarda, I have come to you from the town of the Apostle of Allah (PBUH) for a tradition that I have heard you relate from the Apostle of Allah (PBUH). I have come for no other purpose.
He said: I heard the Apostle of Allah (PBUH) say: If anyone travels on a road in search of knowledge, Allah will cause him to travel on one of the roads of Paradise. The angels will lower their wings in their great pleasure with one who seeks knowledge, the inhabitants of the heavens and the Earth and the fish in the deep waters will ask forgiveness for the learned man. The superiority of the learned man over the devout is like that of the moon, on the night when it is full, over the rest of the stars. The learned are the heirs of the Prophets, and the Prophets leave neither dinar nor dirham, leaving only knowledge, and he who takes it takes an abundant portion.