Richardson writes using the epistolary or letter writing form for his 1740 novel. Pamela tells her story through the series of letters she writes to her parents about her predicament with Mr. B. Later, she continues the letters as a form of diary when she realizes her parents cannot receive them. Epistolary novels were popular in the eighteenth century because they lent an aura of realism to a story. People frequently wrote letters to each other; therefore, it would seem perfectly natural that a novel is constructed as if it were the publication of a "real" cache of letters.

Pamela has been criticized, however, because the vast bulk of the letters are written by her, leading to the question of reliable narration. Can we trust Pamela's version of the story she tells when we have no other account to compare it to? (Richardson solves this problem in later novels, such as Sir Charles Grandison by having key events retold several times in different letters from different people.) 

Clearly, Richardson meant for Pamela to be a trustworthy narrator. The subtitle of the novel is “virtue rewarded,” and Pamela, on one level, is a representation or symbol of "virtue." In this case, "virtue" is primarily understood as retaining one's sexual purity against a wily, predatory aggressor. Beyond that, however, Richardson intends her to be an ideal of goodness and wants the reader to trust her narration.

Yet, as critics have pointed out, Pamela is also structuring the narrative—as any person would—to show herself in the best possible light. While Mr. B., on the contrary, is anything but trustworthy, he points to way letter writing can shade or distort events when he writes to Pamela's father:

Hence, silly girl! her misrepresentations of those innocent familiarities of mine to her, on certain benevolent occasions ...

We also see from Pamela's own account that she can bury her true self under a public self that presents quite differently. For example, she acts with great politeness and modesty to local ladies who treat her poorly, but privately writes of a Mrs. Brooks:

She looked with such a malicious sneering countenance, I cannot abide her.

She likewise surprises Mr. B in her letters by revealing an assertive private self at odds with the self-effacing public self she revealed to him. He says to her that she thinks of herself as “his equal.” This is, apparently, an unforgivable thought for the eighteenth-century man.

As readers in the twenty-first century, we have the benefit of the modern lens. Therefore, we can be more critical of what we deem excusable or permissible. It is true that many marriages were arranged or matches were made for economic convenience. We notice that Mr. B and Pamela’s marriage does not fall into this category: they have, against all odds, fallen in love and married outside of their classes. This match is somewhat disturbing, though, given Mr. B’s predatory actions and infidelity. It is difficult to get over his attempted rape of Pamela, though Richardson’s writing does not reflect any hesitation. He seems to equate virtuosity and femininity with obedience or tolerance. Women are painted as having to endure terrible things and come out graceful, merciful, and understanding. It is puzzling, indeed, that Pamela happily consents to their marriage. Looking at Pamela with a critical lens is important to best understand the climate in which Richardson is writing: it was a time when unwanted sexual advances on women were undesirable yet considered permissible and forgivable.