Yama is meant for controlling the senses.
In order to advance in spiritual understanding, one has to hear from authentic sources about spiritual knowledge. One can understand the reality of spiritual life by following strict regulative principles and by controlling the senses. To have control it is necessary that one be nonviolent and truthful, refrain from stealing, abstain from sex life and possess only that which is absolutely necessary for keeping the body and soul together. One should not eat more than necessary, he should not collect more paraphernalia than necessary, he should not talk unnecessarily with common men, and he should not follow the rules and regulations without purpose. He should follow the rules and regulations so that he may actually make advancement.
ahimsa satya asteya brahmacharya aparigraha yama –Yoga sutra 2.30
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