S. is a contemporary example of an eighteenth-century narrative tradition, a novel in the form of letters. Updike updates the epistolary form by introducing tape-recorded messages. He also limits and controls the narrative by having all the letters come from a single character. In this way Sarah's mind is the stage for all that happens in the novel. Her feelings and thoughts, however compromised and mistaken, are the comedy and drama of Updike's narrative.

Another of Updike's techniques is the frequent repetition of the Hindu vocabulary in vogue at the religious commune. Not only is Sarah given a new name, she also learns a whole new language for dealing with her thoughts and feelings. One source of the guru's power, of course, is his apparent ownership of a foreign and exotic language. Updike clearly has fun by writing his novel in both English and Sanskrit. He even provides a glossary of words for the unenlightened.

The most important precedent for Sarah Worth is Hawthorne's The Scarlet Letter. Updike makes this quite clear by quoting two descriptions of Hester Prynne to serve as an epigraph for his novel. The many echoes of Hawthorne not only challenge the reader to make connections, but they also lend historical depth to Updike's contemporary story.

The subject of adultery is seldom missing from Updike's twelve earlier novels. The success of Couples in 1968 was the occasion for Updike's first appearance on the cover of Time. Adultery and its consequences remain central in the series of novels from Rabbit, Run (1960) to Rabbit at Rest (1990), and the subject even receives a supernatural treatment in The Witches of Eastwick (1984). Updike has explored numerous points of view for adultery in his fiction, but lately, in The Witches of Eastwick and now more thoroughly in S., he has presented the subject from a female perspective, or, some contend, a caricature of such a perspective.

Updike's fascination with Hawthorne's fiction is apparent in much of his recent work. It was the topic of his 1979 lecture at the American Academy of Arts and Letters, and Hawthorne was again on Updike's mind when he wrote about witchcraft and adultery in The Witches of Eastwick. His novels, Roger's Version (1986) and S., are both modern derivatives of The Scarlet Letter. Indeed, the two can be read as different versions of Hawthorne's famous romantic triangle. Both respond to the figure of a minister, a modern Dimmesdale, introduced by Updike as early as 1975 in A Month of Sundays. Perhaps the only point of view that Updike has yet to explore is that belonging to Pearl, although her marriage to wealth and nobility in the Old World is foretold in S.