Moses first wife, Lydia Lamborn, wrote letters that have been preserved. These provide information and details of a kind often missing for those who lived in the frontier regions of North America in the 17th century. On the other hand, the origins of Moses are a bit of a mystery to me. Some family trees have him as the son of a Thomas Marshall (1745-1819 and Ann Cox (1745-1798) who lived in Chester County, PA and were members of the New Garden Quaker Meeting. Other accounts, however, indicate that Moses was born in Germany and spent his early years there.
According to an unverified online source, Moses was present at the Quaker wedding of George Lamborn and Martha Marshal on December 2, 1790, and there there are meeting notes in which Moses is listed in a way that suggests he was considered a family member. Specifically, he is described as being “listed on the right side.” I don’t know whether this refers to a seating arrangement or to the layout of written notes. Be that as it may, it seems he was “on the right side” along with George & Martha Lamborn, Robert Lamborn, Thomas & Ann (Cox) Marshall, Robert Lamborn Jr., Hannah Marshall, Susannah Marshall, David Lamborn, Lydia Lamborn, Ann Pennock, and Pamela Marshall. In 1791, Moses married Lydia Lamborn, and the ceremony was performed by a magistrate rather than in a Quaker meeting. Records of the New Garden Monthly Meeting show that Moses and Lydia were disowned by that meeting on February 4, 1792. 
By 1793 (perhaps earlier) Moses and Lydia had moved west and were living near the Monogahela River in what was then Fredericktown, Washington County, PA. They had two sons, James and John Lamborn. According to The Genealogy of the Lamborn Family, “Judging from old sayings and records we have come to the conclusion that Moses was a blacksmith and followed the trade for a living. For when Lydia Lamborn (24) was being talked to by her father before her elopement with Moses, she said ‘Father, I wouild rather live with Moses Marshall in a corner of his blacksmith shop than with Ennion Cook in a palace.’ This saying is vouched for in Mary Ann Dawson’s (116) statement, who had often heard the expression when quite young, which is conclusive that he was a blacksmith; and when Robert (2) cried out in the night ‘David, David, (20) Tid’s gone!’ he was sending one blacksmith to chase another, as David was also a blacksmith.” 
This same source includes transcriptions of letters written by Lydia, which I’ve reproduced below with only one change to correct a date that was obviously wrong.
After Lydia died, Moses married Mary Adams. Between 1799 and 1827, the had 15 known children: Moses, Lydia, Joseph, Robert, Albert, Benjamin, Charles, Lewis, Thomas, Gallatin, William, George, Mary, Eliza and Permelia. Sometime around 1810, Moses and Mary moved to Columbiana County, Ohio. 
 This information is from a message sent on October 14, 2005 by Allan Gillignham to the RootsWeb PABUCKS mailing list. At the time when this post was first written, that message could be seen at http://archiver.rootsweb.ancestry.com/th/read/PABUCKS/2005-10/1129390536. That URL is no longer valid. However, as of January 2021, that message can be seen at https://mlarchives.rootsweb.com/listindexes/emails?listname=&thread=18453534.
 Gladden, Sanford Charles (1969) The Durst and Darst Families of America, Vol II. Original publisher unknown. Republished 2013 by the Boulder Genealogical Society. Preview of p. 679 with information about Moses Marshall at https://books.google.com/books?id=lmCiBQAAQBAJ : accessed September 19, 2015.