Rhetorical devices are persuasive devices.

In chapter 7, Hester sets out with Pearl to the governor's mansion to plead with him that she should be allowed to keep custody of Pearl. She has heard rumors that people want to remove Pearl from her care under the theory that her adultery makes her an unfit mother.

Hawthorne wants to persuade the reader to be on Hester's side as she makes her way to face the governor. To do that, Hawthorne uses an allusion to the David and Goliath story from the Bible. This puts Hester in the position of a David, the underdog facing a far more powerful opponent. It is a match:

between the public, on the one side, and a lonely woman, backed by the sympathies of nature

However, we also notice Hester's assurance and courage, for to her it seems "scarcely" unequal to go up alone against the combined weight of the community.

Further, in a novel in which nature is often depicted as a good vis-a-vis the artificial and stifling constraints of the Puritan social order, Hester is firmly aligned with nature in the quote above. We feel sympathy for her plight as well as for her as representative of nature: a woman simply wanting to be with her child.

More sympathy is built up for Hester as she encounters narrow-minded people who want to show their disdain for her, even though they know nothing of her as a distinct human being:

Behold, verily, there is the woman of the scarlet letter; and, of a truth, moreover, there is the likeness of the scarlet letter running along by her side! Come, therefore, and let us fling mud at them!

Knowing the hostility of the public at large helps build reader sympathy for Hester by making us feel protective toward her.

Many in number, rhetorical devices are techniques used in order to persuade the reader to consider a character or an object or a topic from a different perspective. Among the most prevalent rhetorical devices are irony and metaphor; irony is used rhetorically in order to disparage humorously or to ridicule an idea or course of action, while metaphor is used primarily to convey a new meaning by connecting it to an existing meaning or idea with which the reader is already familiar.

Irony

In Chapter Vii of The Scarlet Letter, as he describes the reason for Hester's visit to the Governor's mansion, Hawthorne injects a certain irony to the purpose of Hester's visit to the mansion of the governor as he alludes to the supposition that Pearl is a "demon child" who must be removed from her mother. There are any number of people involved in this decision, not the least of whom is the Governor himself. But, not until the question is first discussed by the select men of the community, then publicly discussed, and finally by "statesmen of eminence [who] took sides." After stating the complicated process, Hawthorne writes ironically,

At that epoch of pristine simplicity, however, matters of even slighter public interest, and of far less intrinsic weight that the welfare of Hester and her child, were strangely mixed up with the deliberation of legislators and acts of state.

The period was hardly...earlier than that of our story, when a dispute concerning the right of property in a pig not only caused a fierce and bitter contest in the legislative body of the colony, but resulted in an important modification of the framework...of the legislature.

Clearly, here Hawthorne ridicules the involvement of the Puritan officials in minor matters such as the ownership of a pig, acts which are certainly incongruous with "pristine simplicity."

Metaphor

One of the most significant of metaphors is used in this chapter; it is employed to convey to the reader a new meaning for the scarlet letter by linking it to the existing meaning of the letter on Hester Prynne's bosom:

But it was a remarkable attribute of [Pearl's] garb, indeed of the child's whole appearance, that it irresistibly and inevitably reminded the beholder of the token which Hester Prynne was doomed to wear upon her bosom. It was the scarlet letter in another form: the scarlet letter endowed with life!

Here Pearl is likened to Hester's scarlet letter;according to the metaphor, Pearl is the letter made incarnate.

Scesis Onomaton

Scesis Onomaton is a rhetorical technique that gives emphasis to an idea with an expression of it in generally synonymous phrases or statements. For example,

But Pearl, who was a dauntless child, after frowning, stamping her foot, and shaking her little hand with a variety of threatening gestures, suddenly made a rush at the knot of her enemies, and put them all to flight.

Sonic Devices

Sound devices such as alliteration and cacaphony are used in Chapter Vii in order to emphasize the mood and intensity of the narrative.

Alliteration - This repetition of the initial cosonant sound occurs in this phrase,

...abundantly embroidered in fantasies and flourishes [/f/ sound]

Cacaphony - chaotic and harsh sounding words easily catch the ear of the reader and create images. For instance, in describing the Governor's mansion, Hawthorne describes it decorated with "strange and seemingly cabalistic figures and diagrams, ....