Yesterday I was reading the parshah, and I hit upon a commentary that bowled me over.
Having spent my time down south amongst chassidim (Chabad and Breslov mainly), I'm well-versed in the whole "always be b'simchah" mentality. Or at least, so I thought. But when I saw that Hashem didn't appear to Yaacov a second time until after the mourning for Devorah and Rachel ceased, that made a big impression on me. Specifically, when I learned that the shechinah doesn't rest where there's sorrow, suddenly, a key concept banged me over the head.
If you think about it, our entire lives are supposed to be about enhancing our relationship with our Creator, thereby improving not only ourselves, but the state of our community, our fellow yiddin world wide, and indeed, all of creation. But if we are closed off from Hashem because our frame of mind prevents it, then that purpose remains out of reach. We can easily understand when people comment that to be sad, depressed, or angry cuts us off from Hashem on an intellectual level, and can even relate to feeling cut off at such times. Certainly when in the throes of negative emotion, it is simple to lower ourselves to a base level. That's why psychobabble loves to categorize various negative emotions as "primal", because they debase us to the level that we relinquish our free will. And that's why so much mussar material tries to get us to focus our attention on getting closer to Hashem, to help us overcome the always waiting road to negativity.
Yet if we contemplate this lesson from the parshah, one can also recognize that there are several components to it. First, one needs to remember that negativity renders us animalistic and denies the free will that Hashem gave only us amongst the species. Next, one needs to find a method to help overcome negative thinking. It is this step where I find many books to be lacking, since I find that most of their strategies simply don't work for me. Regardless, if one knows oneself, one can hit upon a strategy that could work, test it out, and fine tune or repeat the process until they find themselves improving. Finally, one needs to recognize that in order to rise higher both in this world and the next, one needs to always remain focussed on one's relationship with Hashem. A tall order, indeed, and one I've touched upon in my previous postings. But the beautiful phrasing of the parshah really rammed home that nugget of truth in such a way that it tied all the loose ends of wisdom/advice ("Everything is always for the best", "Being angry separates you from Hashem", "What's the use of being depressed? This world is so fleeting and you being depressed does nothing to change your lot, so...", etc.) into a useful bow.
In short, by banishing negativity in one's mind, one's heart becomes unfettered and open to Hashem. In turn, one can improve spiritually, and also have one's heart open to help one's family, one's community, even the world.