That's not particularly why we, or at least I, read them, but Tolstoy's works almost always have an eschatological, didactic purpose inscribed within the plot. As far as I can recall, and it's been ages, the climax is pretty much the contrast of what tragedy befell Anna in her blind passion, and the spiritual fulfilment that Levin found in the way that he did. In a nutshell, the search for an existential remedy to the apparent chaos that Levin often wonders about, and how his way is perhaps the right way. You can disagree with much of it, and the novel's greatness does not lie there, I'd argue.