Mishkat ul Masabih #261: ‘Aun reported that ‘Abdullah b. Mas’ud said: There are two avaricious persons who are never contented. The man of learning and the man of the world, but the two are not equal; the man of knowledge increases in submission to God, but the man of the world becomes head strong and defiant. ‘Abdullah then recited: “Nay, man is surely rebellious when he sees himself free from want” (Quran 96:6); concerning the other he cited the verse: Surely those of His servants who are possessed of knowledge, fear God (Quran 35:28) (Darimi).