The record that Buddha founded Buddhist Precepts on ten reasons, can be traced to the `Vinaya-pitaka` of all different sects. Among ten reasons, some are the reasons for the excellence and prosperity of whole Buddhism，and some are the reasons for personal improvement of the practice. The present article mainly uses the material of `Sravakabhumi`，and especially focuses on the subject of how the Buddhist Precepts improve the practice of Meditation.
In `Sravakabhumi`，the requisites of Meditation practice (`samadhi-sambhara`) include the restraint of morality and sense organs, knowing the amount of food，practice of staying awake in the beginning and end of the night，conduct with awareness... and the adequacy of the ascetic. Besides the restraint of morality，(1) the restraint of sense organs, (2) knowing the amount of food，(3) practice of staying awake in the beginning and end of the night，(4) conduct with awareness are also related with Buddhist Precepts.
First of all，"the restraint of morality" is explained into six phrases according to the traditional instruction of Buddhist Precepts. Moreover these six phrases are analyzed by three characteristics and properties. And ointment or perfume and so on are used to admire the merit of Precepts as similes. Next，one's mind is guarded by mindfulness, keeping from the sinful，unvirtous natures flowing into the mind by way of sense organs. This practice is called "the restraint of sense organs".
About "knowing the amount of food"，the practitioner should considerate the purpose of taking food，not for indulgence or fun and so forth, but simply for maintenance，so he eats moderate food not too much, and not too little. Then one purifies his mind from obscuring natures by means of walking and sitting during the day，during the beginning and end of the night，only sleeping in the middle of the night. This is called "practice of staying awake in the beginning and end of the night". At last，"the conduct with awareness" means one conducts himself with awareness while he does every action outdoors and indoors.
Therefore，we can say "mindfulness" and "awareness" are the key words of practice of Buddhist Precepts. And according to the theory of `Yogacara-school`，this two points can also improve the practices of Meditation.
