Christ 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.

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.”

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