What does the word "justification" mean in Paul's sentence in Romans 5:18?
Romans 5:18 - Therefore, as one trespass led to condemnation for all men, so one act of righteousness leads to justification and life for all men.
There is obviously some parallelism going on here. Let me lay out what I see as the parallels:
Therefore, as one trespass led to condemnation (and death) for all men,
so one act of righteousness leads to justification and life for all men.
Justification is a parallel concept to condemnation in this sentence. Condemnation does not describe a moral corruption, but describes a legal sentence issued because of guilt. Criminals are condemned by a judge due to their guilt. Continuing this parallel, it must be that justification is also a legal declaration. Justification is the legal declaration that a person is righteous and innocent of any crimes.
When God justifies us, he forgives our sins and accepts us as righteous. Justification is a legal declaration.
It is not a legal fiction any more than the guilt that we inherit from Adam is a legal fiction. Because Adam is our representative, his guilt is imputed to us and we are born with a guilt problem. In the same way, Jesus is the representative of his church and the righteousness of Jesus is imputed to believers. They are declared righteous on the basis of Christ's righteousness just as the children of Adam are declared guilty on the basis of Adam's sin.
We don't inherit the guilt of Adam; we inherit his fallen and lost
condition. A real, ontological change took place in humankind. The original state of righteousness that Adam possessed was gone, innocence was lost. And the chief and most devastating aspect of that change was spiritual separation from God, sometimes referred to as the "death of the soul". Immediate knowledge of God was lost. Man no longer believed in a God; Adam had become his own "god" in the act of disobeying God's authority, and therefore denying His godhood. In this brave new world man was dead without knowing it, and lost: not knowing where he came from, if anywhere, what he's here for, if for anything, and where he's going afterwards, if anywhere. He is self-righteous now, no longer "God-righteous" as he's no longer subjugated to God; man now does what's right in his own eyes, often with very ugly results. Once man assumes control, sin abounds; self-control is actually
lost. Adam's pride now often motivates man's actions, rather than God. Adam
preferred himself to God as one teaching I'm familiar with put it.
So since a real change, towards injustice/unrighteousness took place in humanity, a real change must take place in man if he's to be
justified, to be made righteous again, as he was created to be.
Man was made for communion with God, 'apart from Whom he can do nothing' (John 15:5). In order for man to be just, he must be freely forgiven of sin first of all, and cleansed of it, but then also made a new creation. Something positive must be added as a necessary component of that justice; he must enter intimate relationship with God. And this can only happen as man comes to
know the true God and this is exactly Whom Jesus came to reveal. But man must be ready to
accept this revelation, this new light; he must understand his need for it, so that faith may come, the faith that establishes union with God. Humankind had undergone a sort of training since Eden, since the Fall, and part of that training consisted in living in a world where the Master is effectively gone away, and experiencing all the evil and sin and meaninglessness and darkness that befalls the world when grace is lacking, and where man's will effectively reigns. We also experience good here, the innate good and beauty of God's creation and of existence itself. Man
knows, by experience, both good and evil in this fallen world, as a result of Adam's sin.
And by revelation and grace God worked with and prepared man through a chosen people down through the centuries until we were ready, just barely perhaps, to receive the full revelation of Himself via the advent of His Son, where grace would now be poured out upon the earth. God had been patiently drawing man towards a
choice, without force just as He wouldn't force Adam to choose rightly, the choice between good and evil, life and death, light and darkness, God or no God.
Now God stood in our presence, now we know the difference, now we can choose. And when we choose
Him, when we're sick and jaded by the darkness and the pride that darkens ourselves and our world and separates us from Him and our fellow man and the rest of creation and even from ourselves we may turn back to Him and He then fills us with Himself, and begins to satisfy that hunger that we've developed for something missing, for truth and righteousness, for Him. He
is the justice we've lost. Our justification entails more than an imputed or declared justice, more than forgiveness, it entails the life of God and grace in us.