
The covenant of works, whether we agree with it or not, has a long pedigree in the Christian tradition. It wasn't as if it appeared on the scene with Ursinus, Fenner, and Cartright. Recently, whilst reading the
Moralia on Job of Gregory the Great (540-604) I found something akin to the covenant of works taught there. And, today whilst reading Boethius' (480-524/5)
De Fide Catholica I found something like it here:
He [God] formed man out of the earth and breathed into him the breath of life ; He endowed him with reason, He adorned him with freedom of choice and established him in the joys of Paradise, making covenant aforehand (praefixa lege) that if he would remain without sin He would add him and his offspring to the angelic hosts. (Boethius, De Fide Catholica, in The Theological Tractates, Loeb Classical Library, trans. H. F. Stewart and E. K. Rand, Cambridge: Harvard Univerity Press, 1968, pp. 56-59)
The actual Latin word for covenant (foedus or pactum) isn't used in the original, the English translators of the Loeb addition added it. The original is praefixa lege ("with a prefigured law"), which introduces the idea of a "law" being given to Adam And, moreover, if Adam obeyed the law then he would have made it ultimately to heaven. In other words, eschatology is there in the garden.
The same basic idea (with different frills) is found in Greg Beale's book The Temple and the Church's Mission. He contends that combining the command for humanity "to fill the earth" in Gen. 1 and Adam to "till the garden" in Genesis 2, Adam and Eve's original mission was to Edenise the entire creation--spread Eden (God's presence, a temple-like idea) over all the earth. Adam, of course, failed. But this same mission has been proleptically achieved by the second Adam in his death and resurrection. The final outcome is protrayed in Rev. 21 where the new creation is depicted as a cube (i.e. the holy of holies): the temple / Eden is co-extentive with the new creation. God's intention for his world has been fulfilled through Christ.