釋氏稽古略 3.36

3.36

丙甲貞觀十年。皇太子承乾問張士衡曰。事佛營福其應如何。對曰。事佛在清淨仁恕。如貪惏（力南反）驕虐。雖傾財事之無損於禍。且善惡必報若影赴形。聖人之言備矣。為君明。為臣忠。為子孝。則福祚永。反是則禍至矣。士衡以此言矯太子心。太子承乾終於失德。貞觀十七年廢承乾為庶人。立晉王治為皇太子。

In the tenth year of Zhenguan, bing[shen] (636), Crown Prince Chengqian asked Zhang Shiheng: "What is the retribution of serving the Buddha and seeking merit?" He replied: "Serving the Buddha lies in purity, benevolence, and forbearance. If one is greedy, arrogant, and cruel, even if one exhausts one's wealth to serve him, it will not diminish calamity. Moreover, good and evil must bring retribution, just as a shadow follows the form. The words of the sages are complete on this. If a ruler is enlightened, a minister loyal, and a son filial, then fortune and prosperity will endure. If one goes against this, then calamity arrives." Shiheng used these words to correct the Prince's mind. Prince Chengqian ultimately lost his virtue. In the seventeenth year of Zhenguan, Chengqian was deposed as a commoner, and Prince of Jin Zhi was established as Crown Prince.