1. Aside from knowing that wrong and injustice must exist in the grand scheme of things even though they won’t prevail in the end, it’s also vitally important to know that if wrong did in fact prevail then G-d’s presence would be further concealed from us (G-d forbid) .
We’d been warned about that a number of times in fact. It’s said that there might be a time when, as G-d put it, wrongdoers will, “seek Me but they will not find Me” (Proverbs 1:25) since He’d be so hidden away; and when wrongdoers will foolishly say “Who sees us and who knows us?” (Isaiah 29:16) because G-d’s presence will have receded further into the background. But that will never come about in fact.
Underlying this idea is the fact that G-d’s presence is hidden from us by degrees all the time in this imperfect world, to be sure. But once we will have yearned long enough for Him, and once everything would have been rectified, He will manifest His presence.
Understand, though, that this implies once again that the system of reward and punishment, justice and injustice, and right and wrong is overridden at this stage over-all by the greater need to allow for wrong and injustice so that it can ultimately be undone, as that will lead to the ultimate revelation of G-d’s full and manifest sovereignty.
2. The reality behind that often hurts, though; for there are times indeed when the righteous must suffer the disgrace and humiliation of having to bear with (seeming) injustice and (truly) underserved hardship. But as Ramchal underscores, that’s only because the situation demands it at the time. True justice will prevail in the end, to be sure, but not until then, sorry to say.
For, as things stand now “the wrongful do prevail, and the hour mocks the righteous”, as Ramchal terms it. As the prophet Amos pointed out there are times when, “the prudent must keep … silent, for it is (simply) a time of evil” (Amos 5:13) and nothing can be done about it for the meanwhile. After all, didn’t our sages underscore the fact that audacity and all sorts of infamies will prevail in the pre-Messianic Era (Sotah 49a)?
3. The point of the matter once again is this, in Ramchal’s own words: “since G-d (ultimately) wants to govern the world as He will when His sovereignty is to be revealed and when we’ll be able to discern the light within the darkness and see wrongdoing turned to goodness, He needs to allow wrongdoing to hold sway (for the meanwhile), to overlook the merits of the righteous”, and to seemingly be unfair and unjust. But that’s the short-term plan alone, for ultimately G-d’s sovereignty — as well as His fairness — will indeed be manifest, the righteous will indeed be lauded as they should, and universal perfection will have been achieved.
We could legitimately ask, though, why it is that some righteous people do reap the rewards of their righteousness here in this world, despite all that. There seems then to be another factor at work as well, but just what is it?
 For Kabbalistic references in this chapter see R’ Shriki’s notes 155-156.
Rabbi Yaakov Feldman has translated and commented upon “The Gates of Repentance”, “The Path of the Just”, and “The Duties of the Heart” (Jason Aronson Publishers). His works are available in bookstores and in various locations on the Web.