In the first half of Chapter 8, we beheld the person of Christ: the God-Man, divinely appointed and equipped for the work of mediation. But a mediator is not appointed merely to be something, but to do something. Who is He, and what did He accomplish? Having established His identity, the Westminster divines now turn to the efficacy, scope, and application of His work. Here we find the bedrock of our assurance: that Christ did not merely make salvation possible for those who might choose Him, but that He actually secured eternal life for those given to Him by the Father.
The Confession teaches that Christ, by His perfect obedience and sacrifice, fully satisfied divine justice and purchased an everlasting inheritance for the elect; that the benefits of this work were applied to believers even before the Incarnation; and that for every person for whom He died, He will certainly and effectually apply that redemption by His Spirit.
The Satisfaction of Justice (WCF 8.5)
The Confession begins this section with the heart of the atonement. “The Lord Jesus, by His perfect obedience, and sacrifice of Himself… hath fully satisfied the justice of His Father.”
Note the two components of His work. First, His perfect obedience (often called active obedience), by which He fulfilled the law we broke (Rom. 5:19). Second, the sacrifice of Himself (passive obedience), by which He paid the penalty we owed. He offered this “through the eternal Spirit” (Heb. 9:14), giving His sacrifice an infinite value. The result was not a partial payment or a down payment, but a full satisfaction of divine justice (Rom. 3:25–26). The debt is canceled.
What did this purchase? “Not only reconciliation, but an everlasting inheritance in the kingdom of heaven.” He bought us out of debt and into a fortune. However, the scope of this purchase is specific: it was “for all those whom the Father hath given unto Him” (John 17:2). The atonement was definite in its intent and particular in its object.
The Retroactive Cross (WCF 8.6)
A common question arises: “If Christ died in the first century, how were people saved in the Old Testament?” The Confession answers that “although the work of redemption was not actually wrought by Christ till after His incarnation, yet the virtue, efficacy, and benefits thereof were communicated unto the elect, in all ages successively from the beginning of the world.”
The cross of Christ is the center of history. Its power radiates forward to us and backward to Adam. Old Testament saints were saved “in and by those promises, types, and sacrifices,” all of which pointed to “the seed of the woman” who would crush the serpent (Gen. 3:15). They were saved on credit, looking forward to the payment Christ would make; we are saved on debit, looking back to the payment He has made. He is “the Lamb slain from the beginning of the world” (Rev. 13:8), being “yesterday and today the same, and for ever” (Heb. 13:8).
The Unity of Action (WCF 8.7)
In the previous article, we discussed the Hypostatic Union—that Christ is one person with two natures. Here, the divines explain how this works in His actions. “Christ, in the work of mediation, acts according to both natures, by each nature doing that which is proper to itself.” Christ died in His human nature, though He cannot die in His divine nature. He was limited in His human nature, yet remains omnipresent in His divine nature.
However, “by reason of the unity of the person,” Scripture sometimes attributes the actions of one nature to the person named by the other. For example, in Acts 20:28, Paul speaks of the church of God “which he hath purchased with his own blood.” God is spirit and has no blood. Yet, because the Person who bled was truly God, we can speak of the blood of God. This doctrine, known as the communicatio idiomatum (communication of properties), upholds the infinite value of Christ’s suffering.
The Certainty of Application (WCF 8.8)
The final paragraph of this chapter is a theological fortress. It asserts the inseparable link between the purchase of redemption and the application of redemption. “To all those for whom Christ hath purchased redemption, He doth certainly and effectually apply and communicate the same.”
This is a vital assertion of Particular Redemption (or Definite Atonement). During the Assembly’s time, and notably through the influence of the English delegation at the Synod of Dort, there were views like Hypothetical Universalism (championed by men like John Davenant). This view suggested that Christ died for all men conditionally to make salvation possible, but God only decreed to apply it to the elect.
The Confession rejects this separation. It binds the purchase and the application together. If Christ bought you, He will come for you. He does not leave His purchase gathering dust on a shelf. For everyone He died for, He is also “making intercession for them” (Rom. 8:34), “revealing unto them… the mysteries of salvation,” and “effectually persuading them by His Spirit to believe and obey.” He governs their hearts and acts in history to “overcoming all their enemies.”
If Christ died for you, your salvation is not merely possible; it is inevitable. The Good Shepherd does not lose His sheep (John 6:37, 39).
Conclusion
Chapter 8 leaves us with a Christ who is a complete Savior. He does not merely offer a theoretical salvation to the world, hoping some might accept it. He is the Mediator who was appointed to save a specific people, who satisfied justice for them, and who now applies that salvation to them with sovereign power. This is a work that cannot fail. Because the purchase and the application are linked by the unbreakable chain of God’s decree, we can rest assured that “he who began a good work in you will bring it to completion at the day of Jesus Christ” (Phil. 1:6).
Key Terms
- Satisfaction: The doctrine that Christ’s obedience and death fully satisfied the demands of God’s holiness and justice, paying the debt of sin that we owed.
- Virtue and Efficacy: The power and benefit of Christ’s work. The Confession teaches that while the historical act of redemption happened at a specific time, its virtue (power to save) applied to believers throughout all history.
- Communicatio Idiomatum: (Latin: “Communication of Properties”) The theological principle that whatever is true of either nature of Christ (human or divine) can be truly predicted of His one Person.
- Particular Redemption (Definite Atonement): The doctrine that Christ’s death was intended to secure the salvation of the elect alone.
- Hypothetical Universalism: A view (rejected by the Confession’s formulation) that Christ died for all men to make salvation possible, but that the effective application is limited to the elect. The Confession asserts that purchase and application are co-extensive.