That Veasey guy is kind of a weasel. Not only is he dishonest and indulgent, he is also vengeful and so self-interested that he is willing to murder his own lover instead of just telling the community that he behaved badly. Why? Because killing her is an offense against a God he does not really believe in; religion is just a method through which is able to use his skill for lying to earn money. He says all the right things to become powerful in the community, and when that power is threatened, he begins to demonstrate archetypal evil.
Notice that Inman is pitted against Veasey and easily defeats him, but then loses in the long run when Veasey betrays them on the battlefield. That shows good and evil at play, because they alternative one-upping each other. Next to the treacherous and deceitful Veasey, Inman's heroic nature stands out by contrast. The question of the book is therefore a kind of Odyssey; will Inman make it back to the love of his life? Ada doesn't even recognize him when he does finally show up, another indication that he is the archetypal hero, because his journey was so difficult, it changed him.
In the end, the crisis between good and evil, life and death, is resolved, and Inman finds his way back into the arms of his true love. But, that reunion is short-lived because in almost no time, the hero is killed. What does that signify, that the hero succeeds but only enjoys his reward for a short time? The answer is somewhat existential; he managed to create new life, a daughter who survives his death. Remember that the novelist has not created more death than necessary; Inman is human and therefore mortal from the first page to the last page, but in the context of the story, his death happens after the conception of his daughter. In that daughter, he will live on.
