When she composed the journal, Knight was a 38-year-old married woman and keeper of a boarding house in Boston with some experience as a copier of legal documents.

In crossing the Thames River in a ferry boat that carried both passengers and their horses, she wrote in an entry dated “Thirsday, Octobr ye 5th”: “Here, by reason of a very high wind, we met with great difficulty in getting over—the Boat tos’t exceedingly, and our horses capper’d at a very surprising Rate, and set us all in a fright.” The following day, after traveling for miles over roads that were “very bad, incumbered with rocks and mountainous passages,” Sarah Knight came to “a bridge under which the river ran very swift, my horse stumbled, and very narrowly escaped falling into the water, which extremely frightened me.” As for room and board, Sarah Knight spent an evening with the Congregationalist minister in New London, “where I was very handsomely and plentifully treated and Lodg’d.” The minister, she noted, was “the most affable, courteous, Genero’s and best of men.” Such experiences, however, were offset by others less wholesome.

On being shown to her room, “a little Lento Chamber furnisht amongst other Rubbish with a High Bedd and a Low one […] down I laid my poor Carkes (never more tired) and found my Covering as scanty as my Bed was hard.” Before crossing a particularly hazardous river, Knight cannot rid herself of thoughts of drowning, writing, "The concern of mind this relation sett me in: no thoughts but those of the dang'ros River could entertain my Imagination, and they were as formidable as varios, still Tormenting me with blackest Ideas of my Approaching fate–Sometimes seeing my self drowning, otherwhiles drowned, and at the best like a holy Sister just come out of a Spiritual Bath in dripping Garments.

Near the end of the journey, she has a rather close call when she writes, "But in going over the Causeway at Dedham the Bridge being overflowed by the high waters coming down I very narrowly escaped falling over into the river Hors and all wch twas almost a miracle I did not.

She explains in her straightforward manner that "[t]he Rodes all along this way are very bad, Incumbred with Rocks and mountainos passages, wch were very disagreeable to my tired carcass.

The small diary of her Boston–New York journey passed into private hands and lay undiscovered until 1825 when it was published posthumously as The Journal of Mme Knight by Theodore Dwight.

[6] The journal is valuable as a history of the manners and customs of the time, and is full of graphic descriptions of the early settlements in New England and New York.

[11] In the widowed years of her life, Sarah Kemble Knight left Boston for good and moved to New London to live near her married daughter.

Furthermore, Knight's detailed descriptions of New York, New Haven, and the many small settlements she travels through across Connecticut, shed light on colonial life at the turn of the 18th century.

Knight's diary has also been important in the field of women's history and literary recovery, both of which are movements that seek to recover narratives often forgotten or neglected in favor of more mainstream, canonized works.

Stephens asserts that "By recognizing the mythic implications of Madam Knight's Journal, even at the expense of its mimetic and outwardly historical impact, we are able to place the work more clearly in the fruitful tradition of colonial American, and particularly New England, literature...Identification of the individual mythic allusions is only a matter of reading, but seeing the tantalizing pattern they fall into is an indication that this innocent and rough-mannered journal has meanings that a literal reading cannot guess at.

"[14] By reading the Journal as a mythical account, Stephens hopes to align Knight's work with the narrative style of Nathaniel Hawthorne.

She unpacks this tightly bound moment with the following solvent prose: Fair Cynthia, all the Homage that I may Unto a Creature, unto thee I pay; In Lonesome woods to meet so kind a guide, To Mee's more worth than all the world beside.

Some Joy I felt just now, when safe got or'e Yon Surly River to this Rugged shore, Deeming Rough welcomes from these clownish Trees, Better than Lodgings with Nereidees.

Knight's knowledge of business and determination is apparent early in her account of her journey when she writes about an exchange concerning payment for an escort.

She tells the woman attempting to get more money from her simply that she “would not be accessary to such extortion.”[18] In the end, Knight stands her ground and is able to bypass the negotiator, deal directly with the would-be escort, and arrange a price she feels is fair.

"[25] She also describes the previously mentioned country gentleman as "spitting a Large deal of Aromatick Tincture, he gave a scrape with his shovel like shoo, leaving a small shovel full of dirt on the floor, made a full stop, Hugging his own pretty Body with his hands under his arms, Stood staring rown'd him, like a Catt let out of a Baskett.