In Srimad-Bhagavatam (7.13.8) it is said, granthan naivabhyased bahun na vyakhyam upayunjita: “One should not read many books, nor should one try to make a profession of reciting many books, especially if one is a devotee.” One must give up the ambition to be a learned scholar and in this way earn a worldly reputation and financial facilities. If one diverts his attention to studying many books, he cannot fix his mind in devotional service, nor can he understand many scriptures, for they are full of grave statements and meanings. In this connection Srila Bhaktisiddhanta Sarasvati Thakura gives his opinion that those who are attracted to studying many kinds of literature concerning various subject matters, especially fruitive activities and philosophical speculation, are deprived of unalloyed devotional service because of their splayed attention.

From Srila Prabhupada’s purport to CC Adi 16.11