Edwards's tone is threatening, and he tries to convince his listeners to repent for their sins and return to God immediately by instilling fear. He uses horrible descriptions of the eternal fate that would await them if God decided to let them fall. He emphasizes that God could make this decision at any time. Edwards says, "'There is nothing that keeps wicked men at any one moment out of hell, but the mere pleasure of God." He calls God's will "arbitrary" in that God has no obligation to continue to preserve wicked people, and he could, at any moment, decide to stop.
Furthermore, Edwards argues that it is basically inevitable that we will fall without God's pleasure in restraining us. He says that we are "always exposed to destruction; as one that stands or walks in slippery places is always exposed to fall." The sinner can do nothing to prevent himself or herself from slipping right down into Hell's fire, and can only hope and pray that God will prevent it. In fact, the devil
stands ready to fall upon them, and seize them as his own, at what moment God shall permit him [....]. The devils watch them; they are ever by them at their right hand; they stand waiting for them, like greedy hungry lions that see their prey, and expect to have it, but are for the present kept back. If God should withdraw his hand, by which they are restrained, they would in one moment fly upon their poor souls.
This imagery is particularly frightening, again, and conveys Edwards's threatening tone, describing sinners as prey for terrible predator devils. Threats like this, I imagine, would convince many people to change their ways. Because the sermon has been retained, it seems clear that it made a significant impression on its audience.