Often times the question is asked, since Hashem is so good and loves each and every one of us with boundless and endless love, will He really punish me for a few small sins?
Chzal tell us אמר ר' חנינא מאן דאמר רחמנא וותרן יתוותרן בני מעויי - R' Chanina said, "If one says Hashem is a 'vatron', i.e. One who lets misdemeanors slide, may that person's intestines become loose and unravelled." (Shekalim 14a)
At first glance the punishement of יתוותרן בני מעויי (yisvatron bnei me'oyi) is a play on words for saying Hashem is a 'vatron'. However, after proper study of the meforshim we see that it goes much deeper.
The Taklin Chadetin explains why it is so bad to think Hashem lets aveiros be (however 'minor'), and why indeed He doesn't. While we can only perceive of our actions having small, sometimes minute, local effects, in reality every deed that a Yid does brings repercussions of enormous magnitude - both in the visible, physical world, and even more so in the spiritual world.
Our mortal minds are so very limited, and our vision so very restricted, that it is hard for us to even grasp this concept, yet it is so very real. When one transgresses even the 'tiniest' aveiroh one creates the most humongous rips in the very fabric of the world. Entire spiritual worlds are destroyed and spiritual-earthquakes of the greatest force reverberate throughout the universe. [Of course when we do a miztvah the opposite occurs; we unleash wellsprings of fortune and sustenance.]
There is good reason why we cannot perceive all the far-reaching effects of our deeds. Since the purpose of our creation is to vanquish the Yetzer Horah, there has to be a challenge. Had we been able to see and hear what joy and abundance we bring to the world by our mitzvos, versus the destitution caused by our aveiros, it wouldn't have been possible to ever do an aveiroh, thus defeating the purpose.
Hashem, by virtue of being the Creator and Sustainer of all that is in existence, knows exactly how great are the repercussions of every tiny deed a Yid does, for better or for worse. Therefore He cannot let even the tiniest misdemeanour pass, because every single mitzvoh and every single triumph over the Yetzer Horah is needed for entire creation to be complete in all its glory.
The intestines are a paradigm of this idea. Despite the extraordinary length of the small intestine (over 23 feet!), every single inch is necessary for it to function properly. When a person l"a has even a small part cut out for due to illness, they will very often need to take vitamin supplements for the rest of their lives, for the shortened intestine cannot do its job adequately.
When someone says Hashem is a vatron, i.e. He won't mind if I'm not completely as I should be, let him contemplate life with a portion of the (seemingly superfluous) intestines missing. Then apply this thought to ruchniyus.
Since Hashem is so good, will he not let things pass? Absolutely not! In fact it is because He is so good and he wants our spiritual self to be complete, and in a complete world with vast abundance, that He cannot overlook even the tiniest aveiroh.
One must bear this in mind when faced with a nisoyon. On the one hand how great it is when one manages to overcome his/her Yetzer Horah, and what immense pleasure Kavyochol derives from that, but on the other hand how devastating it is to the entire creation when one fails.
[Of course if one has already fallen chalilah, then one has to remember never to give up.]
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