In 1876 he was asked to rule on a challenge to election returns in the hotly disputed gubernatorial campaign, eventually won by Democrat Wade Hampton and ending Republican domination in the state.

His mother was one of 22 children of Jonas Phillips and his wife Rebecca Machado, was from a prominent Portuguese-Jewish family in Philadelphia, Pennsylvania.

Upon completing his early education in Charleston, Moses attended South Carolina College in 1819 and graduated in 1823.

At the urging of Judge J. S. Richardson in Clarendon, Moses was persuaded to practice law in Sumterville in a neighboring county; it was also in the rapidly developing Piedmont area of the state.

This area became developed for the commodity crop of cotton and was dominated by large plantations based on enslaved African-American labor.

From the beginning, he applied two principles - to avoid prosecution of a man in the criminal courts if his life was in danger, and on the civil side, to support only those suits that had real merit.

He quickly established a good reputation in Sumterville and was elected as captain of a company of cavalry, the Claremont Troop.

From 1850 to 1865, Moses was a member of the board of trustees at South Carolina College; he taught law at the institution for several years afterward.

Moses married Jane McLellan (also spelled McClenahan) of Chesterfield, who was a devout Methodist and avid gardener.