Francis Roberts wrote the 1,700 page puritan magnum opus on Covenant Theology (1657).  His section on the nature of the Mosaic Covenant is the fullest and best, Scriptural and theological discussion of the topic that Church History has graced us with, given here for the first time in a contemporary and easily readable edition.

Roberts, representing the majority, historic Reformed viewpoint, argues at length that the Mosaic Covenant was not a covenant of works, but was a further unfolding of the Covenant of Grace, with a peculiar Law-emphasis in its administration in order to drive sinners to Christ. Please enjoy: 

Roberts, Francis – ‘Of God’s Giving the Law on Mt. Sinai as a Covenant, and that of Faith’  1657  90 pp., being Book 3, Chapter 4, Aphorism 2 of The Mystery and Marrow of the Bible: God’s Covenants with Man, with an Introduction and Extended Outline