Delving into it even more so we see that while the reward and punishment system we’d depicted above is certainly rooted in Divine Justice , it’s also based on the realities of the human condition .
For as we explained , our actions affect our very beings  aside from our spiritual status, making us either more perfect and exalted or sullied and faulty, in perfect proportion to those actions .
Now, the mostly righteous person who managed to accrue a lot of spiritual splendor  and stature has nonetheless also become somewhat sullied from the few sins he’d committed, and he’s thus not yet ready to attach himself onto G-d’s presence. So G-d mercifully decreed that he’d be purified by the kinds of trials and tribulations calibrated to remove the impurity from him . Then he’d be pure enough to enjoy that great reward.
Just know, however, that one would have to experience the exact degree of purification that would correspond to his status.
Know, too, that sometimes the cleansing process can’t be carried on a physical level so it must be done on a spiritual one . It’s just that we can’t fathom the very many calculations that go into all of that.
 I.e., it’s rooted in the idea that the fair and just thing to have happen is for the good to be rewarded for their selfless dedication to the good and right, and the wrongful to be punished for their selfish disregard of it. The point of the matter, though, is that there’s another, higher aim than that, which is seeing to it that as many individuals as possible be able to bask in G-d’s presence in the world to come, as was pointed in 2:2:3 above.
 This refers to our very human impurities as discussed below.
See 1:4:2 as well Adir Bamarom p. 341.
 See 1:4:4,10.
 … inside and out, in that they affect our physical beings much the way that good or bad food affects our bodies, and good or bad habits affect our personality, and the like.
The point is that being and doing good allows a certain impalpable still point of holiness and perfection to nestle and glow in our being while being and doing bad allows a certain opaque, noisome, and unctuous blemish to fester there.
 See Zohar 1, 24a and 131b; 3, 86b, 99b, and 128a; and Sh’nei Luchot HaBrit 1, 26b.
 See Klach Pitchei Chochma 32 for a discussion of this phenomenon.
 See 2:2:9 and 2:3:8 below and Da’at Tevunot 40, 54 as well as Berachot 5a, Zohar 3, 153a.
That’s to say that, as all-encompassing as it is and touching upon all elements of our being as it does, suffering — both the kind we experience in life or in the Afterlife — undoes all blemishes and utterly scours away at all stains, much the way weeping purges sorrow, and admitting fault unburdens the heart.
 This goes to explain why there needs to be an Afterlife in the first place: to allow for the sorts of processes that can’t be carried on within the physical, emotional, or psychological realms we mortal beings imagine would be enough to purify — as well as to reward — us.
(c) 2015 Rabbi Yaakov Feldman
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