Using the Categories of God’s Image and the Functions of Covenant Mediator
Johnson’s volume is worth its weight in gold in my estimation because of the section he provides on categories for understanding Christ as head of the new creation and mediator of the new covenant who restores mankind to the image of God. He presents this as a way for preachers to locate key themes in OT passages to guide them to a fuller understanding of how Christ fulfills those themes to be used in presenting Christ as the Covenant Mediator who, by God’s cosmic plan, restores fallen humanity to the image of God.
1) The Cosmic Plan: Creation, Fall, Redemption, Consummation
Johnson insists that all preachers must become familiar with the contours of redemptive-history and the divine purpose underlying them. All texts of Scripture properly understood must be “related to God’s cosmic plan” of “erasing sin and its effects… [and] through grace carrying us (and creation with us) even higher and deeper into knowing him and glorifying him” than would ever have been possible had man not fallen. Johnson guides us to consider 1) how in creation God bestowed the divine image on man “in knowledge, righteousness, and true holiness” (LBC 9.2, cf., Eph 4:24, Col 3:10); 2) how in the Fall the divine image was defaced—knowledge, righteousness, and holiness each being features of God’s image; 3) how in redemption the new creation was begun and the divine image restored; and how in consummation, the new creation will be completed and the divine image perfected in man in “in knowledge, righteousness, and true holiness” (Eph 4:24, Col 3:10).
Amazingly, Johnson shows how each of Christ’s covenant-mediatorial offices (prophet, priest, and king) correspond to a feature of the divine image distorted in fallen man—thus making him the perfectly suitable savior for those he represents.
Moreover, Johnson expounds the OT concepts of covenant lord and servant, showing how Jesus, as covenant Lord, is the center of God’s initiative to rescue, redeem and renew (thus being the source of Scripture’s indicatives); and showing how Jesus as the “ultimate Covenant Servant” [is] the embodiment of obedience to the law imperatives of God. Thus, Christ is the covenant Lord and Servant who as mediator is also Prophet, Priest, and King—able by his person and work to restore in man the image of God and bring his people into right relationship with God. The dimensions of God’s image, knowledge, righteousness, holiness (Eph 4:24, Col 3:10), correspond to “the mediatorial roles and offices that God ordained to reestablish rightness in these dimensions.” The following chart illustrates the relationships and functions inherent in Christ’s person and work:
|Dimension of the image of God||TRUE KNOWLEDGE||RIGHTEOUS AUTHORITY||HOLY RELATIONSHIP|
|Parties to the covenant|
|LORD||Speaks truly, illumines hearts||Rules justly, defends, judges||Consecrates, receives worship|
|MEDIATORS||PROPHET: Hears, delivers the word to God’s people||KING: Executes the Word, judges wisely & justly, defends God’s people||PRIEST: Teaches the Word, atones and prays for God’s people|
|SERVANT||Hears and trusts God’s Word||Obeys God’s word||Pursues purity & peace in reconciled relation to God & God’s people|
Johnson reminds us that justification by grace through faith in Christ’s 1) active obedience, and 2) his passive obedience is not the complete picture of redemption; we must also preach (to ourselves and others) 3) sanctification by grace through faith, that is, Christ transforming us to restore us to God’s image. As Johnson aptly writes,
our exposition of imperative texts does not stop with what Christ has done for us; is also extends to what Christ, by His Word and Spirit, is doing in us. In the context of his achievement of our redemption the Spirit’s gracious, persistent application of redemption in our sanctification is good news as well.
Thus Johnson gives preachers a useful map that lays out the landscape of common themes and concepts germane to the OT and helpful for expounding not only how Christ fulfills the OT, but how he can be applied to contemporary hearers.
 Johnson, Him We Proclaim, 239-271.
 ibid., 243, 44.
 ibid., 251.
 ibid., 258.
 ibid., 268, which is also fleshed out by the Heidelberg catechism, 12.31-32.
 ibid., 261.
 ibid., 267.