Mahabharata 8.33.38

न भवान्क्षत्रधर्मेषु कुशलोऽसीति मे मतिःब्राह्मे बले भवान्युक्तः स्वाध्याये यज्ञकर्मणि

na bhavānkṣatradharmeṣu kuśalo'sīti me matiḥbrāhme bale bhavānyuktaḥ svādhyāye yajñakarmaṇi

Our plain-language meaning of this verse is waiting for scholar review.