For a brāhmaṇa, austerity and learning are certainly auspicious, but when acquired by a person who is not gentle, such austerity and learning are most dangerous.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
तपो विद्या च विप्राणां निःश्रेयसकरे उभे । त एव दुर्विनीतस्य कल्पेते कर्तुरन्यथा
tapo vidyā ca viprāṇāṃ niḥśreyasakare ubhe | ta eva durvinītasya kalpete karturanyathā
SB 9.4.70