This is the classic statement of Covenant Theology at the end of the 17th Century. Witsius steers an irenic course between Voetsius and Cocceius. The first volume deals with Covenant Theology proper while the second volume analyzes the various types and shadows of the Old Testament.
Generally, covenants signify a mutual agreement between parties, with respect to something (43). A covenant of God, furthermore, “is an agreement between God and man, about the way of obtaining consumate happiness,” including sanctions (45). This covenant comprises three things: a) Promise; b) condition; c) sanction.
While it is a free agreement between God and man, man really couldn’t say no. Not to desire God’s promises is to refuse the goodness of God, which is sin. Witsius views the CoW as probationary, yet Adam wouldn’t have “earned” the reward per any intrinsic merit. The reward is rooted in God’s covenant, not in man’s merit.
Doctrine of God
God’s knowledge of future things cannot be conceived apart from his decreeing them (141). The creature acts in concurrence with God’s action. All things come from God. There is only one first cause (I.8.15). If something could act besides having God as its cause, then there would be multiple first Causes, which is polytheism.
God and sin. If all beings come from God, and even though sin is privation of being, it, too, is a kind of entity, then it also arises from God’s plan (para 22)
Chapter 1: Introduction to the Covenant of Grace
Definition: a compact or agreement between God and the elect sinner, God on his part declaring his free good-will concerning eternal salvation, and every thing relative thereto, freely to be given to those in covenant, by, and for the mediator Christ; and man on his part consenting to that goodwill by a sincere faith (2.1.5).
Chapter 2: Of the Covenant between God the Father and Son
The covenant of redemption is between God and the Mediator. The will of the Father, giving the Son to be the Head and Redeemer of the elect; and the will of the Son, presenting himself as a Sponsor or Surety for them (2.2.2). Christ’s suretyship consists in his willingness to undertake to perform that condition (2.2.4).
The exegetical foundation is in Zech. 6.13. There is a counsel of Peace between God and the Branch.
Covenant and Justification: God the Father, through Christ’s use of the sacraments, sealed the federal promise concerning justification (para 11). Christ’s baptism illustrates the sealing of the covenant from both sides.
Chapter 1: Of the Covenant of God with the Elect
The contracting parties are God and the elect (281). The son is not only mediator but testator, who ratified the covenant with his death. Are there conditions in the covenant of Grace? Earlier divines like Rutherford spoke a qualified “yes,” though Witsius removes himself from that language. Condition: that action which gives a man a right to the reward (284).
The substance of the decalogue is the same as the moral law (p. 165). When God gave the decalogue to Israel, he published some reasons annexed to it that were peculiar to Israel alone (176). There is in some sense a repetition of the Covenant of Works in Sinai (IV.4,47). However, it was not repeated simpliciter. Carnal Israel embraced it as a covenant of works (Rom. 9.31). Sinai contains no promise of grace.
The Old Covenant
Witsius contrasts the promises made to Abraham with the stipulations of the Sinaitic Covenant. In Sinai God did not promise to give the people a heart to obey (337). And it is to this covenant, and not to the Abrahamic or Davidic covenants, that God contrasts with the New Covenant.
This is the classic statement. Witsius gets somewhat speculative in the second volume, but the first volume definitely rewards careful study.