In order to understand Ramchal’s statements we’d need to begin with this. The Kabbalists speak of two sorts of movements in the universe: from Heaven down to earth, known as Ohr Yashar (“Light [that emits] straight [and heads downward]”), and from earth back up to Heaven, known as Ohr Chozer (“Light [that emits] backward [or, heads back up]”}. The point is that while we have been presenting the Ohr Yashar dynamicin our discussions of how the universe derived from the Divine, the Ohr Chozer dynamic also comes into play.
For, put plainly, the world wasn’t only created to remain in the present state forever; it will someday return to the pristine oneness with the Divine Presence it enjoyed before the world was created . And it — as well as we ourselves — will experience certain specific stages along the way.
The point is that all of that will come about through a sort of “implosion” of the Ohr Yashar process that Ari has been laying out for us (and which Ramchal has been explaining in Klach) that is the great Ohr Chozer phenomenon. Let’s see how the Partzuf of Attik and others illustrate all this.
 See 4:6 above and note 16 there.
(c) 2014 Rabbi Yaakov Feldman
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