“Behold My Servant, Whom I uphold; . . . I have put My Spirit upon Him; He will bring forth justice to the nations” (Isa 42:1).
God is bound to purpose and to do what His absolute holiness requires. He has no attributes, no will, no sovereignty, above this law of His being. He cannot deny Himself, He cannot acquit the guilty without an atonement.
“ . . . Who forgives . . . Yet He will by no means leave the guilty unpunished” (Exod 34:6-7).
So, Paul says, when God offered Jesus as a sacrifice to bear the punishment for sin, it was "to show God's righteousness” (Rom 3:25), demonstrating that He dealt with sin appropriately in His desire and determination to provide and offer forgiveness to men.
“But now, apart from the Law, the righteousness of God has been manifested, . . . even the righteousness of God through faith in Jesus Christ for all those who believe; . . . being justified as a gift by His grace through the redemption which is in Christ Jesus; Whom God displayed publicly as a propitiation in His blood through faith. This was to demonstrate His righteousness, because in the forbearance of God He passed over the sins previously committed, for the demonstration, I say, of His righteousness at the present time, so that He would be just and the Justifier of the one who has faith in Jesus” (Rom 3:21-26).
“Yet we ourselves esteemed Him stricken,
Smitten of God, and afflicted.
But He was pierced through for our transgressions,
He was crushed for our iniquities;
The chastening for our well-being fell upon Him,
And by His scourging we are healed.
The LORD has caused the iniquity of us all
To fall on Him.
By His knowledge the Righteous One,
My Servant, will justify the many,
As He will bear their iniquities.
Because He poured out Himself to death,
And was numbered with the transgressors;
Yet He Himself bore the sin of many” (Isa 53:4-12).
God’s righteousness is exhibited in the death of Christ -- the evidence that God is neither indifferent to sin, nor regards it lightly. His holiness must find expression in His condemnation and punishment of sin.
God’s patience in delaying wrath is ruled by His holiness.
The Bible tells us that God is "slow to anger" (Ps 103:8). He delays in executing His wrath in order to leave people more time to repent (see 2 Pet 3:9-10).
Right furnishes the rule and law for love, but it is not true that love furnishes the rule and law for right. Holiness is independent of love as an attribute and it is superior to it. If it were otherwise — if God’s holiness ever made an exception for the sake of love, He would no longer be holy.
(Spotlight 9, Lesson 10 in Doctrine 101: Learning about God)