Samuel Rutherford was a very prominent Scottish member of the Westminster Assembly, which sat in the 1640s.  He is most well-known for his famous Letters, which have gone through several reprintings and are a wonderful example of the best of Puritan piety and pastoral counsel.  He is also remembered for his defense of Presbyterian church government at the Assembly, against both the Independents and the Erastians.

 

However, he did publish an extensive treatise on the covenant.  It appeared in 1655, as was entitled The covenant of life opened, or, A treatise of the covenant of grace.  In the eleventh chapter, Rutherford deals with several abberant views on the Mosaic covenant.  First he deals with the Amyraldian view (espoused first by John Cameron, and later by Bolton), which argues that the Mosaic covenant is not a covenant of works or a covenant of grace, but rather a third "subservient" covenant.  This view is rejected by the Standards, as well as the Formula Consensus Helvetica.  Second, he deals with those who make the Mosaic covenant a covenant of works, completely different from the covenant of grace.  This is the view of all Lutherans, as well as a very small minority of Reformed theologians.  It is also rejected by the Standards (WCF 19:1-2, LC 101, etc, but we will deal with that issue elsewhere).  Finally, he deals with the Arminian view.  It is similar to the Amyraldian view, in that it also argues for three covenants entirely distinct in substance.