One Biblical image of God is that of the just judge. People stand before a judge to get justice. God metes out justice, too. The problem is that His justice brings with it His wrath and punishment upon sin and sinners. His law hunts us down like a bounty hunter and drags us before the judge for sentencing. The law reveals our sins. The law reveals our ulterior motives. The law shames us. We have approached God seeking justice and reimbursement for what has been done against us, and instead we have received justice and reimbursement upon ourselves for our many sins.
The law reveals to us a heavenly Father, a divine Judge, who is angry and stern. His holiness cannot bear to be in the presence of sin or sinners. His justice demands that sinners be punished and put to death. His verdict upon us is “guilty” and we are subsequently given the death sentence. There is no way to appeal this decision. The gavel has rapped down. The court has been adjourned. God will quickly bring His justice against us.
The law always shows us the wrathful nature of God. But where is God’s mercy? Surely, God must love us.
God the Father does indeed love us. He loves us more than anything in all the universe, but we could never come to recognize the Father’s favor and grace were it not for Christ, who is the mirror of His Father’s heart (BKS 660.64 [38-42]; Large Catechism). Apart from Christ, we see nothing but an angry and terrible judge (BKS 660.64 [42-44]). But neither could we know anything of Christ, had it not been revealed by the Holy Spirit (BKS 660.65 [44-47]).
Christ is the mediator between God’s wrathful justice and us. Christ stands in the middle, between the fury of God’s punishment on sin and us who are about to bear that terrifying fury. Our heavenly Father’s wrath strikes down Christ, on the cross, and unleashes upon Him the full destructive nature of God’s anger over sin. Here we see God’s great mercy, for He desires to punish Christ so that we will be spared His tremendous fury. Christ paid the price for our forgiveness, and so on account of Him we are justified in the sight of God.
BKS: Die Bekenntnisschriften der evangelisch-lutherischen Kirche, 12th Edition © 1998 by Vandenhoeck & Ruprecht.