user12710: I just don't understand how morally good actions, can reliably change the state of mind positively over time, in the case where the mind state is negative. For example, let's say there was a hypothetical girl who wanted to purify her mind, but was always agitated, resentful and frustrated. How would practicing the five precepts, make her calm and peaceful?

user2282: There's a term called "habit energy", or "underlying tendency", the hidden force that influences our motive to do/speak/think in wholesome or unwholesome ways. As simple analogy is a chain smoker would tend to carry on his unhealthy habit due to it being persistently re-inforced for so long. But if s/he has the strong will to replace the bad habit with good habits of eating healthy, exercising frequently, etc., then overtime the s/he'll be able to  build up a new wholesome "habit energy" strong enough to overpower the older unhealthy one. Practice senses restraint thru the Five Precepts are just like that.

user14789: It is mostly the opposite of 

How would practicing the five precepts, make her calm and peaceful?

the result of sati sampajana is the respect of the precepts, not the contrary. This is what puthujjanas struggle a lot to understand. Any puthujjana can follow the 5 precepts for 5 minutes, but it is sati and sampajana a which makes this hold in the long term. 

user43: Well, it seems obvious to me now, but it wasn't always, that our immoral impulsive behavior, both of possessive type and of repulsive type, comes from emotional hangups, so giving in to those hangups feeds them, or creates circumstances that feed them indirectly. So, if this immoral behavior comes from the mind, then by managing behavior we learn to control what? 
Anyone who tried the precepts knows they are impossible to keep without paying attention to one's mind and emotions. Precepts force us to control our external behavior, which requires controlling our mind, that's it. No magic. 

12710: <p>I just don't understand how morally good actions, can reliably change the state of mind positively over time, in the case where the mind state is negative. For example, let's say there was a hypothetical girl who wanted to purify her mind, but was always agitated, resentful and frustrated. How would practicing the five precepts, make her calm and peaceful?</p>
 2282: <p>There's a term called "habit energy", or "underlying tendency", the hidden force that influences our motive to do/speak/think in wholesome or unwholesome ways. As simple analogy is a chain smoker would tend to carry on his unhealthy habit due to it being persistently re-inforced for so long. But if s/he has the strong will to replace the bad habit with good habits of eating healthy, exercising frequently, etc., then overtime the s/he'll be able to  build up a new wholesome "habit energy" strong enough to overpower the older unhealthy one. Practice senses restraint thru the Five Precepts are just like that.</p>
 14789: <p>It is mostly the opposite of </p>

<blockquote>
  <p>How would practicing the five precepts, make her calm and peaceful?</p>
</blockquote>

<p>the result of sati sampajana is the respect of the precepts, not the contrary. This is what puthujjanas struggle a lot to understand. Any puthujjana can follow the 5 precepts for 5 minutes, but it is sati and sampajana a which makes this hold in the long term. </p>
 43: <p>Well, it seems obvious to me now, but it wasn't always, that our immoral impulsive behavior, both of possessive type and of repulsive type, comes from emotional hangups, so giving in to those hangups feeds them, or creates circumstances that feed them indirectly. So, if this immoral behavior comes from the mind, then by managing behavior we learn to control what? </p>

<p>Anyone who tried the precepts knows they are impossible to keep without paying attention to one's mind and emotions. Precepts force us to control our external behavior, which requires controlling our mind, that's it. No magic. </p>
