He also owned houses on State and Ann streets, a country estate in Roxbury, Massachusetts, a chaise, considerable china, silver, glassware and furniture, over 30 paintings/drawings, several hundred books and pamphlets, and a gold watch.

He served as executor of the wills of numerous prominent Massachusetts citizens of the time, including Governor William Dummer.

After the Battle of Lexington and Concord started the Revolutionary War, the Massachusetts militia laid siege to Boston, trapping the British Army and the citizens of the city inside.

However, he was not condemned as a loyalist, and his valuable properties in Boston and country estate in Roxbury, Massachusetts were not seized by the revolutionary government.

[10][11][12] However, a decade and a half before, Goldthwait and a group of other businessmen had been appalled at the writs of assistance that the crown had started issuing to clamp down on colonial smuggling.

[13][14][15] In 1761, Goldthwait and a group of other outraged Boston businessmen engaged lawyer James Otis, Jr. to challenge the writs of assistance in court.

Otis gave the speech of his life, making references to Magna Carta, classical allusions, natural law, and the colonists' "rights as Englishmen".

A young lawyer, John Adams, was in the packed courtroom, and was moved by Otis's performance and legal arguments.