One of the difficulties of biblical interpretation is that the Bible often speaks in metaphor and parables. And it is utterly contentious as to when a particular passage should be understood as such. These differences in understandings divide entire religious movements.
For instance, I once witnessed a discussion between a Protestant and a Catholic where the Protestant said "you eat a metaphor during communion." And the Catholic replied "no YOU eat a metaphor; I eat the living God."
Ben Franklin's writings on revelation suggest he was heavy on the metaphorical and parabolic understanding such that it's debatable whether he believed any of the Bible was inspired in a "literal" sense, as opposed to a book that contained much wisdom and "truth" in a different sense.
The clearest statement Franklin EVER gave on his understanding of revelation (during the time in his life after he moved from deism to theism) was in his letter to John Calder where he said "that the[re are] several Things in the old Testament impossible to be given by divine Inspiration, such as the Approbation ascrib’d to the Angel of the Lord, of that abominably wicked and detestable Action of Jael the Wife of Heber the Kenite. If the rest of the Book were like that, I should rather suppose it given by Inspiration from another Quarter, and renounce the whole."
As it relates to Franklin, religion & Bible, we know this much:
1. The Bible teaches a future state of rewards and punishments;
2. Other world religions teach a future state of rewards and punishments;
3. Ben Franklin believed in a future state of rewards and punishments.
Ben Franklin did NOT (at least provably not) believe in a future state of rewards and punishments because the Bible said so. Rather, Franklin's reason and common sense told him this teaching was true and Franklin valued the Bible and other religions to the extent that they reinforced this teaching.
On the concept of the nature of those rewards and punishments, Franklin was no hellfire preacher. And when Franklin recites scripture that relates to the teaching of a future state, we err if we conclude he held to a literal meaning.
For this post I will examine one of those examples, that of Lazarus and the rich man. First, among Bible believers it's debatable whether such should be read in a literal sense. This page by Bible believing Christians, for instance, makes a good case that such a tale is NOT meant to be read literally, but parabolically.
Franklin too, as I read him, endorse a parabolic reading of the text. He, in his "Appeal for the Hospital" said:
[A]lso, the rich Man, is represented as being excluded from the Happiness of Heaven, because he fared sumptuously every Day, and had Plenty of all Things, and yet neglected to comfort and assist his poor Neighbour, who was helpless and full of Sores, and might perhaps have been revived and restored with small care, by the Crumbs that fell from his Table, or, as we say, with his loose Corns.—I was Sick, and ye Visited me, is one of the Terms of Admission into Bliss, and the Contrary, a Cause of Exclusion:...[Bold face mine.]
Notice that Franklin terms the rich man as merely being "excluded from the Happiness of Heaven." If you read the story literally, it's much more than that; the rich man appears to be tortured. It's obvious that Franklin rejects this understanding.
Indeed, as I have shown before, Franklin espoused a biblical method that permits him to "understand" scripture in a sense agreeable to his reason, common sense and notion of benevolence of the deity. He admitted the hard orthodox could cite scripture in a straightforward way to reach results that seemed extremely unfair and made God look cruel. And he then he noted, he had "the right to look out for another Sense of the Passage in Question, which will not contradict the clear Decisions of Reason." He did this so "the Almighty," is not represented "as stern, arbitrary, inexorable, ..."
It's obvious to me that's what Franklin did with the story of Lazarus and the rich man. If taken to represent the larger truth of a future state of rewards and punishments, that we must watch how we treat people in this life because cosmic justice awaits in the next life, such a story can be lauded.
If however, the story is taken to mean there really was this rich man and this is exactly how God will treat him for eternity, Franklin didn't buy it (at least he shows no evidence his understanding of the story held to that "Sense of the Passage in Question.")