《史记·三十世家·晋世家》
国君以太子为军队统帅是错命官职，统帅军队会使太子丧失威严，将来怎么重用他呢？ 
君失其官，率师不威，将安用之？ 
For the monarch to appoint the crown prince as the commander of the army is to appoint the wrong official. Being the commander of the army will make the crown prince lose his authority. How can he be reused in the future?