釋氏要覽 2.25

2.25

即周禮第九肅拜也。又是內法下品禮也。書云揖如磬折。若仰首直身叉手不謹。即慢甚也。故孔子曰。為禮不敬吾何以觀之。

This is the subai [solemn bow], the ninth bow in the Zhouli. It is also the lowest grade of etiquette in the Buddhist tradition. The Book of Documents states: Bowing like the bend of a chiming stone. If one holds the head high, straightens the body, and clasps the hands carelessly, it is exceedingly haughty. Therefore Confucius said: "If one performs ritual without reverence, how can I bear to look upon it?"