The class can be found here.
All in all, Adam and Eve’s sin had tremendous and catastrophic consequences that we’re still contending with.
While they were purposefully created imperfect  so that they could fairly contend with the choice between doing the right or wrong things as we indicated , and to achieve perfection on their own , that imperfection was further aggravated by their sin. They and everyone else were demeaned in the process . And it has thus become harder for us, their descendants, to achieve perfection.
For, G-d had originally seen to it that it would have been easy enough for us to make the right choices and to achieve perfection. But it became that much more difficult for us to achieve it to this very day. And humanity has sunk deeper and deeper yet in the mire, as yet another step has been added to the process: we must not only go ahead and achieve perfection on our own, but we also have to backtrack and achieve what Adam and Eve didn’t.
 This calls for a thorough explanation of the creation of the universe. That would necessarily draw us far afield, so let’s offer the following inadequate but terse explanation.
In the very beginning (before all beginnings), all there was, was G-d Almighty Himself. At a certain point He decided to create reality, but in order for it to exist it would need to somehow be separate from Him (otherwise it would be subsumed in His Being, and couldn’t exist after all). So G-d allowed for a supernal “empty space” to come about that would be devoid of Him, so to speak, which is the first instance of un-G-dliness and imperfection. (See the beginning of Eitz Chaim for this recondite idea known as Tzimtzum, as well as Ramchal’s Klach Pitchei Chochma 30 for its connection to humankind).
Like everything else, humankind is an offshoot of this phenomenon, and it’s thus intrinsically un-G-dly and imperfect. Ramchal is thereby underscoring the fact that Adam and Eve (like everything else other than G-d Himself) suffers from an intrinsic imperfection — aside from the ones they brought upon themselves with their sin.
 See 1:3:2 above.
 See 1:2:2 above.
 See note 1 to 1:3:6.
Ramchal and many others speak of the negative matter accrued upon us as a result of Adam and Eve’s sin as a kind of spiritual “filth”. See Da’at Tevunot 72 and Adir Bamarom 2, p. 54.
(c) 2014 Rabbi Yaakov Feldman
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