The Westminster Confession of Faith, Chapter VII, Article II states:
This is God’s primal relationship to humanity for the Westminster Confession of Faith style of Calvinism; a style that has been replicated and re-iterated by many theologians and biblical exegetes since its inception. The primary implication of this is not an anthropological one (although that is present), but an implication that reposes in a doctrine of God. What this article implies about God’s primal nature reflected in his relating to humanity is that it is a forensic legal relationship; as such, in order for relationship with God to be sustained humanity must keep God’s Law (i.e. covenant of works). Since humanity did not keep God’s Law they must suffer the penalty of their Law-breaking. But since God is a gracious God, he steps into his legal punitive arrangement with humanity and establishes what the Westminsters called the Covenant of Grace, note Articles III and IV:
III. Man, by his fall, having made himself incapable of life by that covenant, the Lord was pleased to make a second, commonly called the covenant of grace; wherein He freely offers unto sinners life and salvation by Jesus Christ; requiring of them faith in Him, that they may be saved, and promising to give unto all those that are ordained unto eternal life His Holy Spirit, to make them willing, and able to believe.
IV. This covenant of grace is frequently set forth in scripture by the name of a testament, in reference to the death of Jesus Christ the Testator, and to the everlasting inheritance, with all things belonging to it, therein bequeathed.
In this scenario God graciously steps in and provides himself, in the Son, as the Law-keeper who will not only keep the Law (active obedience) but bear its consequences in the elect’s stead (passive obedience).
What I want us to notice though is how this all gets framed, and how discordant it is with the biblical account and Self revelation of Jesus Christ. God’s primary reason for establishing a Covenant of Grace is in order to sustain and meet the conditions of his relationship to humanity. His relationship, in this framework, to humanity is not based upon his love for them, but instead it is based upon the condition of humanity keeping his Law; it is based upon a legal-forensic-juridical relationship. And God comes in Christ under these conditions, because his people have become sinners. God, in this scenario, does not come simply because he loves his creatures; instead he comes to uphold his justice and legal character as God.
This picture looks something like what Douglas Campbell calls Thomas Schreiner’s approach to reading Paul; except Campbell labels Schreiner’s position as Melanchthonian (which we will have to explain later). Here is how Campbell responds to Schreiner’s view on God’s relationship to humanity in salvation, and as corollary, his response to the Westminster Confession of Faith’s Covenant of Works/Grace approach (Campbell would make a fine Evangelical Calvinist); he writes:
The trouble starts, as we have already seen, when Schreiner states, “Before we can speak of salvation … we must discern why salvation is needed.” And it just needs to be said here clearly that this is not true, and his other material tells us why. God acts electively, before humans know anything (a strong Reformed claim). He does so, moreover, not because people are sinful, but because he loves them. Indeed, Ephesians says this clearly, the key text–which is often overlooked–reading “… in love he predestined us for adoption through Jesus Christ [and for him]” (Eph. 1:4b-5a). Ephesians then goes on to tell us at some length that God desires to create people and to have fellowship with them from and for eternity. Because he loves them, he will intervene to rescue them when they have fallen into trouble, and the order of his actions here is crucial.
There is not impossible “plan A” followed by a remedial “plan B” in this Reformed elective understanding of God as Melanchthonians suggest, and mercifully so! This would suggest that God was lacking in foreknowledge, or fundamentally inconsistent and fickle, or perhaps powerless – all appalling theological options. There was only ever plan A, which was and is elective, rooted in the positive divine purposes, and this will stay on track and ultimately triumph despite human corruption, stupidity, and sinfulness – something Calvin appreciated better than most. In short, a proper understanding of God’s election in Christ entails that Schreiner does not need to ask the question that launches the secondary discordant system that disorders his broader description of Paul. But a proper respect for human sinful depravity reinforces this judgment to refrain from asking an anthropocentric question and beginning theology there as Melanchthon does.
Campbell’s response makes clear what the primary reason for God’s incarnating in Christ was. For the Apostle Paul the motivation was not to keep the integrity of God’s legal character upheld in relation to his creation; instead, according to Campbell, the reason God came was the reason he was always going to incarnate, because he loves humanity and desires to have an intimate Father-Son by the Holy Spirit relationship with them. His coming certainly dealt with the pollution of humanity; but his primary motivation for coming always came from his always already reality of Triune love, the same reality which motivated God to create in the first place.
The conclusion from this brief sketch of things is that there have been whole systems of theology and biblical exegesis created to sustain a paradigm about God that is not consonant with who God is, and has revealed himself to be. The reality is, is that ever before he created the tree of the knowledge of Good and Evil, he created; and this fact alone demonstrates that God’s primal relationship to creatures is primarily grounded in his life of love and grace not Law. Is obedience an important expression of love for the other? Indeed! But obedience to the Law was never intended to be the bases for our relationship with God, just as a loving relationship between spouses in marriage is not based upon obedience to house-hold codes.
 Douglas A. Campbell, “Response To Thomas R. Schreiner,” in Four Views On the Apostle Paul: Thomas R. Schreiner, Luke Timothy Johnson, Douglas A. Campbell, and Mark D. Nanos (Grand Rapids, MI: Zondervan, 2012), eds. Stanley N. Gundry and Michael F. Bird, Loc. 848, 855, 861 kindle.
 This idea of a singular plan “A” and the idea that God was always planning on incarnating even without the Fall is called the Scotist thesis in medieval theology, and I’ve written more about that here.