As the marriage was in 1746, I would have thought James would be born later than 1705. The first baptisms of a James Digby in Essex after 1700 on freereg are below.
Parents George & Susan do not seem to fit the names of James children
James DIGBY Baptism 10 Jan 1720 Essex Panfield : St Mary the Virgin : Parish Register (7 miles SW of Castle Hedingham, Essex )
This seems more realistic, if James was born in Essex. Parents James & Sarah
(James was James & Margaret’s eldest son, Sarah was their second daughter, so this fits the English naming pattern)
James DIGBY Baptism 11 May 1722 Essex Belchamp Otten: St Ethelbert and All Saints: Parish Register (4 miles N of Castle Hedingham)
Colin