When he brought them out of Egypt, Yahweh made a covenant with his people from Mt. Sinai. It is often called the Mosaic or Sinaitic covenant. The details and terms of this covenant are found in various parts of Exodus and Numbers and also in Leviticus and Deuteronomy (and other parts of Scripture). I appreciate how Charles Hodge talks about the Mosaic covenant as it relates to the covenant of works and the covenant of grace. He first mentions that the Mosaic covenant had much to do with the covenant of grace:
We have the direct authority of the New Testament for believing that the covenant of grace, or plan of salvation, thus underlay the whole of the institutions of the Mosaic period, and that their principal design was to teach through types and symbols what is now taught in explicit terms in the gospel. Moses, we are told (Heb. 3:5), was faithful as a servant to testify concerning the things which were to be spoken after.
That’s a very common view in Reformed theology, that the covenant of grace underlies the Mosaic covenant. I certainly agree with Hodge. But what about the covenant of works and the Mosaic covenant? Here’s Hodge again:
Besides this evangelical character which unquestionably belongs to the Mosaic covenant, it is presented in two other aspects in the Word of God. First, it was a national covenant with the Hebrew people. In this view the parties were God and the people of Israel; the promise was national security and prosperity; the condition was the obedience of the people as a nation to the Mosaic law; and the mediator was Moses. In this aspect, it was a legal covenant. It said, “Do this and live.” Secondly, it contained, as does also the New Testament, a renewed proclamation of the original covenant of works. It is as true now as in the days of Adam, it always has been and always must be true, that rational creatures who perfectly obey the law of God are blessed in the enjoyment of his favor; and that those who sin are subject to his wrath and curse. …If he [a man] will not be under grace, if he will not accede to the method of salvation by grace, he is of necessity under the law.
In a very helpful following section, Hodge goes on to mention several different ways the NT talks about the Mosaic economy. I’ll post that at some other point. For now, I wanted to share Hodge’s balanced explanation of what the Mosaic economy had to do with the covenant of works and the covenant of grace.
The entire section is found in Charles Hodge, (1997). Systematic Theology (Vol. 2, p. 375). Oak Harbor, WA: Logos Research Systems, Inc.
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