Isaac was a Hebrew patriarch of the Old Testament. He was the son of Abraham and husband of Rebecca.
When Isaac was a child God commanded that his father, Abraham, sacrifice him. He was saved by divine intervention. This dramatic test of Abraham's faith was taken to prefigure God's sacrifice and saving of his own son, Christ. The incident is sometimes represented in the background of works where the primary subject is Christ (see for example El Greco's 'Christ driving the Traders from the Temple').
Rebecca was chosen by Eliezer, on behalf of Abraham, to be Isaac's wife. Claude painted the celebrations which accompanied the marriage of the couple in 'The Mill'.