In comparing Jonathan Edwards' Personal Narrative and Parts One and Two only of Benjamin Franklin's Autobiography, use four quotes to demonstrate a preference for one over the other.
Which work you prefer is a matter of personal choice, but there is no doubt that the style and voice of the works differ. Edwards, who largely writes about his own journey towards faith in God, has a distinctive style that can at times be jarring but that is always memorable. For example, he writes of his days as a non-believer:
But in process of time, my convictions and affections wore off; and I entirely lost all those affections and delights and left off secret prayer, at least as to any constant performance of it; and returned like a dog to his vomit, and went on in the ways of sin. Indeed I was at times very uneasy, especially towards the latter part of my time at college; when it pleased God, to seize me with a pleurisy; in which he brought me nigh to the grave, and shook me over the pit of hell.
Edwards is able to capture his experience with vivid similes, such as returning to his disbeliefs like "a dog to his vomit." His writing also conveys a sense of drama, as he believes that he has been afflicted with pleurisy because of God's wrath against him, and he includes a vivid image of himself being dangled over the pit of hell. This type of image is similar to the types of images he presents in his famous sermon, "Sinners in the Hands of an Angry God." He makes a deep and lasting impression on his reader about God's power.
Later, when he writes about his conversion, his style is similarly vivid:
The first instance that I remember of that sort of inward, sweet delight in God and divine things that I have lived much in since, was on reading those words, I Tim. i:17. Now unto the King eternal, immortal, invisible, the only wise God, be honor and glory for ever and ever, Amen. As I read the words, there came into my soul, and was as it were diffused through it, a sense of the glory of the Divine Being.
He relates his conversion in stirring terms, and he provides the metaphor of being diffused with a sense of glory, as if he were diffused with a type of liquid, to convey the totality and power of his experience. While Edward's religion, Calvinism, is associated (perhaps unfairly) with a sense of coldness, his experience of it is very personal, dramatic, and emotional.
Franklin's autobiography, in contrast, has a kind of stilted, canned quality. He presents his successes in a way that does not admit to personal fault and that projects a sense of arrogance, as much as he tries to be humble. For example, in the following passage from Part I, he writes:
And now I speak of thanking God, I desire with all humility to acknowledge that I owe the mentioned happiness of my past life to His kind providence, which led me to the means I used and gave them success. My belief of this induces me to hope, though I must not presume, that the same goodness will still be exercised toward me, in continuing that happiness, or enabling me to bear a fatal reverse, which I may experience, as others have done, the complexion of my future fortune being known to Him only in whose power it is to bless to us even our afflictions.
While he is also writing of God's divine providence, as Edwards does, Franklin writes more about himself and his success. There are other passages in his narrative that you can find that convey this same self-satisfaction and braggadocio. His writing also lacks the drama and style of that of Edwards, as it is more straightforward and uses less figurative language.