user11674: Now this is often raised whenever a monk teaches and talks about the five precepts. They often say that these are not, like in the judeo christian faith, commandments and that no higher entity or something will punish one. Now to my question: These monks belief in post mortem rebirth (I do not) and they therefore employ wrong speech regarding the aspect of punishment. One is getting punished (hell realm etc.) if one is not in line with the precepts (based on their view on post mortem rebirth).
Can anyone explain this phenomena?

user13335: Although I was not present, it sounds like the monks were not referring to "punishment" in the sense of being "punished for sins" by some divine arbitrator.  Instead, the fruits of karma (cause and effect) ripen and cause what we name a "rebirth" in a higher, lower, or equal realm.  In the Buddhist tradition, anything that is not a human rebirth is perceived as not desirable as the human experience is the one most able to approach enlightenment.
Since the fruits of karma come about from one's own actions, it would be self-inflicted "punishment" - perhaps not the best choice of words but not wholly inaccurate.  Is it punishment if you fall to your death after jumping off a cliff?  We might say it is gravity "punishing" an individual in such a situation - such is the verbiage here.  In Buddhism, it is up to you to experience your own karma.  Nobody judges you for it or can change it for you, but karma will allow you suffer the consequences of your decisions.  
Interestingly enough, the Buddha contradicted himself on a number occasions depending on the crowd he was speaking to.  This was due to the skillful use of words to explain something to his listeners in a way that they could understand.  Have you thought that perhaps the monks in this case were employing skillfulness in a similar manner to describe these things in such a way that it would cause you to wrestle with these concepts?
As an aside, it sounds like the real problem may be with the question of rebirth and a desire to object to any language centered around it.  If indeed rebirth existed, then would you still have an issue?  There are a number of highly realized individuals throughout history that have claimed either experience or insight into other planes of experience.
That said, I have wrestled with the concept of rebirth in the past and can't say that I have solved it but I would put forth a few thoughts:

The base (most subtle in Buddhist terms) awareness we experience seems to be the exact same awareness that animals and even insects experience.  I am not talking about intellect or cognitive abilities but the simplest base sense of "experiencing the world around us".  Personally, meditation on this concept has helped.
"Hells", "Heavens", and the like could simply be states of mind.  In some ways, we are born, live, and die moment to moment as each moment causes the next, and a bad mindstate in any given moment could indeed be considered "hellish".
Modern neuroscience has not been able to pin down if human experience is indeed purely physical or if it is perceived by the brain.  I have corresponded with numerous neuroscientists on Quora and have found a consensus that this is still the elephant in the room.  Sure, we can see how the brain uses nerves to send a signal to my fingers to tap the keys on my keyboard.  But the actual experience that decides to initiate the tapping?  That is still elusive.
Modern quantum physics involves reality coming into being when there is an observer.  Perhaps our experience is the observer when a quantum wave collapses?  If so, it is independent of the physical universe it observes.  (On yet another side note, the overlap between Buddhism theory of mind and quantum physics is a fascinating study)

And so on, I could keep going, but I think you can see there is much more here than a simple materialist approach can resolve.

11674: <p>Now this is often raised whenever a monk teaches and talks about the five precepts. They often say that these are not, like in the judeo christian faith, commandments and that no higher entity or something will punish one. Now to my question: These monks belief in post mortem rebirth (I do not) and they therefore employ wrong speech regarding the aspect of punishment. One is getting punished (hell realm etc.) if one is not in line with the precepts (based on their view on post mortem rebirth).</p>

<p>Can anyone explain this phenomena?</p>
 13335: <p>Although I was not present, it sounds like the monks were not referring to "punishment" in the sense of being "punished for sins" by some divine arbitrator.  Instead, the fruits of karma (cause and effect) ripen and cause what we name a "rebirth" in a higher, lower, or equal realm.  In the Buddhist tradition, anything that is not a human rebirth is perceived as not desirable as the human experience is the one most able to approach enlightenment.</p>

<p>Since the fruits of karma come about from one's own actions, it would be self-inflicted "punishment" - perhaps not the best choice of words but not wholly inaccurate.  Is it punishment if you fall to your death after jumping off a cliff?  We might say it is gravity "punishing" an individual in such a situation - such is the verbiage here.  In Buddhism, it is up to you to experience your own karma.  Nobody judges you for it or can change it for you, but karma will allow you suffer the consequences of your decisions.  </p>

<p>Interestingly enough, the Buddha contradicted himself on a number occasions depending on the crowd he was speaking to.  This was due to the skillful use of words to explain something to his listeners in a way that they could understand.  Have you thought that perhaps the monks in this case were employing skillfulness in a similar manner to describe these things in such a way that it would cause you to wrestle with these concepts?</p>

<p>As an aside, it sounds like the real problem may be with the question of rebirth and a desire to object to any language centered around it.  If indeed rebirth existed, then would you still have an issue?  There are a number of highly realized individuals throughout history that have claimed either experience or insight into other planes of experience.</p>

<p>That said, I have wrestled with the concept of rebirth in the past and can't say that I have solved it but I would put forth a few thoughts:</p>

<ol>
<li><p>The base (most subtle in Buddhist terms) awareness we experience seems to be the exact same awareness that animals and even insects experience.  I am not talking about intellect or cognitive abilities but the simplest base sense of "experiencing the world around us".  Personally, meditation on this concept has helped.</p></li>
<li><p>"Hells", "Heavens", and the like could simply be states of mind.  In some ways, we are born, live, and die moment to moment as each moment causes the next, and a bad mindstate in any given moment could indeed be considered "hellish".</p></li>
<li><p>Modern neuroscience has not been able to pin down if human experience is indeed purely physical or if it is perceived by the brain.  I have corresponded with numerous neuroscientists on Quora and have found a consensus that this is still the elephant in the room.  Sure, we can see how the brain uses nerves to send a signal to my fingers to tap the keys on my keyboard.  But the actual experience that decides to initiate the tapping?  That is still elusive.</p></li>
<li><p>Modern quantum physics involves reality coming into being when there is an observer.  Perhaps our experience is the observer when a quantum wave collapses?  If so, it is independent of the physical universe it observes.  (On yet another side note, the overlap between Buddhism theory of mind and quantum physics is a fascinating study)</p></li>
</ol>

<p>And so on, I could keep going, but I think you can see there is much more here than a simple materialist approach can resolve.</p>
