尝有所荐，其人来谢，安世大恨，以为举贤达能，岂有私谢邪？

尝有所荐，其人来谢，安世大恨，以为举贤达能，岂有私谢邪？

这是『汉书·张安世传』上的话，意思是： （汉宣帝的大司马，车骑将军，富平侯张安世）曾经有一次想上级部门推荐了某个人，那个被推荐的人后来跑来感谢张安世的推荐，张安世非常生气，认为推荐社会贤达能人（是责任义务），怎么能够搞的像私底下交易后酬谢的那种行径呢？

英文翻译：

Once, Anshi Zhang (who was a noble and high ranking official by then ) gave an recommendation to someone. That person came to thank Zhang afterward. To everyone's surprise, Zhang was very upset. He insisted that it was his duty and responsibility to introduce talents to the government and shouldn't be recompensed as a deal-making underneath the table.

请问问题是什么呢？