Ramchal offers the following well known Kabbalistic principle in his comments to Petach 62 (our subject at hand) which is that, “every (supernal) level has a corresponding level in regard to human service”. That’s to say that everything that occurs in the human experience corresponds to and must occur in the supernal realms, and vice versa.
As such, “since humankind’s service is entirely based on free will, wherever there’s free choice, there has to be the possibility of (both) damage and repair, (as well as) reward and punishment (in the supernal realm).”
And so we learn in this Petach that in order for there to be human free will and subsequent reward and punishment, the Sephira system was erected upon the foundations of MaH which allows for goodness and Tikkun, and BaN which allows for rah and its consequences, both of which need to exist together.
Thus we’re taught in the Petach itself that all things having to do with defects — i.e. whatever allows for defilements and their subsequent penalties — are rooted in the Sephirot of BaN, whereas all things having to do with Tikkun, which come to repair these defects, are rooted in the Sephirot of MaH.
But each level needs to be comprised of both MaH and Ban for the sake of the sort of governance needed, i.e., to allow for free will. As a consequence, all elements of rah exist there under the auspices of BaN, while all elements of goodness exist there under the auspices of MaH .
 Also see Klallei Pitchei Chochma v’Da’at 8.
(c) 2013 Rabbi Yaakov Feldman
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