You will get many answers to this. There are many extraordinary passages in the work. For my bet, I think that the prayer Hector offers the gods in favor of his son is really powerful. It is at this moment that we see Hector at his best and we see what tragedy is. The ancient definition of tragedy is what drives the entire work. This idea is rooted that tragedy is the collision between equally desirable, but ultimately incompatible courses of action. In the end, human beings are reduced to the agonizing decision of choice without any sort of redemption in either end. Hector represents this beautifully in Book VI. Andromache, as a good wife, begs her husband to not fight and Hector realizes that while he does not want to fight and die, he also does not want to live as a coward. In the end, this becomes the fundamental tragic predicament. Hector's prayer to the gods for his son is a moment where there is some level of comedy to this tragic end, punctuated by the son who is terrified of his father in his battle armor. Even a prayer to the gods cannot resolve Hector of his pain and the brutal agony of his narrative. This passage highlights that beautifully.