《辽史·列传·卷三十四》
大康初，枢密使耶律乙辛因为奸诈阴险窃夺权柄，被出为中京留守，孟简与耶律庶箴上表祝贺。
大康初，枢密使耶律乙辛以奸险窃柄，出为中京留守，孟简与耶律庶箴表贺。
In the early years of Dakang, the military governor Yelü Yixin was impeached for his treacherous and sinister plot to seize power. He was sent to be the governor of Zhongjing. Mengjian and Yelushu celebrated with a congratulatory message.
<s>[INST] Identify the key themes in this Classical Chinese text and explain them in English: 大康初，枢密使耶律乙辛以奸险窃柄，出为中京留守，孟简与耶律庶箴表贺。 [/INST] In the early years of Dakang, the military governor Yelü Yixin was impeached for his treacherous and sinister plot to seize power. He was sent to be the governor of Zhongjing. Mengjian and Yelushu celebrated with a congratulatory message.</s>
Identify the key themes in this Classical Chinese text and explain them in English: 大康初，枢密使耶律乙辛以奸险窃柄，出为中京留守，孟简与耶律庶箴表贺。
user
In the early years of Dakang, the military governor Yelü Yixin was impeached for his treacherous and sinister plot to seize power. He was sent to be the governor of Zhongjing. Mengjian and Yelushu celebrated with a congratulatory message.
assistant