"Sinners in the Hands of an Angry God"
"There is laid in the very nature of carnal men a foundation for the torments of hell. There are those corrupt principles, in the reigning power in them, and in full possession of them, that are seeds of hell fire. [ ... ] The corruption of the heart of man is immoderate and boundless in its fury; and while wicked men live here, it is like fire pent up by God's restrains, whereas if it were let loose, it would set on fire the course of nature; ... it would immediately turn the soul into a firey oven, or a furnacne of fire and brimstone."
Here, Edwards states that "unsaved" people are naturally on a path of destruction. Their principles are weak and they are completely governed by their impulses alone. This complete deference to desire is overwhelming in people, but is still somewhat restrained by God. If God weren't holding it back, it would fully consume them.
I found this particular quote striking because it reveals a bit of the struggle that Edwards himself went through. He admits in his "Personal Narrative" that he struggled with complete piousness and that he many times returned to living "...In the ways of sin." (Personal Narrative, P. 466) In this passage, you are able to see a bit of the philosophy that Edwards developed around the nature of people and sin. This passage illustrates his belief that it was in people's nature to live in what he considered sin. Coupled with his admission of repeatedly back-sliding himself, you are able to see how his faith and experience had led him to his conclusions on human nature.
Something else this reveals is the sort of language and style that Edwards liked. This passage is full of strong, passionate "fire" words. Each sentence contains either a very strong word closely linked with fire or an actual alternative form of fire. "Fury" and "hell" and "fiery oven" Edwards drives his imagery into your mind over and over again with these words, you can practically imagine someone spontaneously combusting in the church!
The peek into Edwards' mind and philosophy coupled with the explosive imagery make this particular passage stand out.