大唐西域記 2.19

2.19

致敬之式，其儀九等：一發言慰問，二俯首示敬，三舉手高揖，四合掌平拱，五屈膝，六長踞，七手膝踞地，八五輪俱屈，九五體投地。凡斯九等，極唯一拜。跪而讚德，謂之盡敬。遠則稽顙拜手，近則嗚足摩踵。凡其致辭受命，褰裳長跪。尊賢受拜，必有慰辭，或摩其頂，或拊其背，善言誨導，以示親厚。出家沙門，既受敬禮，唯加善願，無止跪拜。隨所宗事，多有旋繞，或唯一周，或復三匝，宿心別請，數則從欲。

There are nine methods of showing outward respect—(1) by selecting words of a soothing character in making requests; (2) by bowing the head to show respect; (3) by raising the hands and bowing; (4) by joining the hands and bowing low; (5) by bending the knee; (6) by a prostration; (7) by a prostration on hands and knees; (8) by touching the ground with the five circles; (9) by stretching the five parts of the body on the ground.
Of these nine methods the most respectful is to make one prostration on the ground and then to kneel and laud the virtues of the one addressed. When at a distance it is usual to bow low; when near, then it is customary to kiss the feet and rub the ankles (of the person addressed).
Whenever orders are received at the hands of a superior, the person lifts the skirts of his robes and makes a prostration. The superior or honourable person who is thus reverenced must speak gently (to the inferior), either touching his head or patting his back, and addressing him with good words of direction or advice to show his affection.
When a Śramaṇa, or one who has entered on the religious life, has been thus respectfully addressed, he simply replies by expressing a good wish (vow).
Not only do they prostrate themselves to show reverence, but they also turn round towards the thing reverenced in many ways, sometimes with one turn, sometimes with three: if from some long-cherished feeling there is a call for marked reverence, then according to the desire of the person.