What does it mean to be good at the public court but too strict in the private room?

It means to praise a person's advantages in public and highlight his abilities and reputation in court; to correct and advise his shortcomings and faults in private.

Source: "Zeng Guofan's Family Instructions"

Enlightenment: Form a general atmosphere of promoting kindness in society, praise the merits and strengths of others, and praise the achievements and progress of others Extensive dissemination and praise can encourage more people to join this virtuous cycle model and effectively promote social progress.

Extended information:

Zeng Guofan followed Cheng-Zhu Neo-Confucianism throughout his life, but he did not blindly worship Cheng-Zhu Neo-Confucianism. In fact, he also absorbed many ideas from other branches of Confucianism in the Song and Ming Dynasties. Neo-Confucianism in the Song and Ming dynasties was actually divided into three academic schools: Qi, Neo-Confucianism and Xinxue.

Zeng Guofan also gradually saw the limitations of Cheng-Zhu Neo-Confucianism in his political practice and military struggle. In this situation, Zeng Guofan showed a tolerant academic attitude towards the study of mind. Regarding the academic debate between Cheng-Zhu Neo-Confucianism and Lu-Wang Xinxue, he believed that in the dispute between the two schools, we should adopt their similarities, avoid their differences, promote their strengths, be inclusive, promote their strengths and avoid their weaknesses, and promote the development of Confucianism.