Rhetorical: Alma has begun by noting that restoration of body and soul is required by eternal justice. He now expands that concept, and includes the judgment as a part of the restoration. Modern theology would see the judgment as separate from physical resurrection, but for Alma it was a part of the same concept. The judgment also restored in the next life an arrangement that began in this life.
In this life the body and soul are together, and they are separated by death. The restoration brings the separated body and soul together again, but in a new and permanent formulation. This model for the nature of the next life serves Alma as a model for the form of judgment that we will receive.
God judges men according to their works and their hearts. If their works and hearts were good in this life, then good is restored to them. If their works and hearts were evil, evil is restored to them. This is a different way of looking at the results of the judgment, but it is different only in perspective, not in essential nature.
The concept of restoration that Alma uses deals with the transition between death and the rising of the dead. This transitional period is a time when what we are is temporarily different. The physical death creates a separation of body and soul. By analogy, our death might also create a separation of our souls from our actions, since we are removed from the realm of earthly action. For Alma, just as our body is restored to us, our essential natures cultivated in this life will also be restored to us. If we were good people before God in this life, so shall we be in the next life. If we were antagonistic to God, if we were evil, so shall we be in the next life.
While not couched in terms of Alma’s doctrine of restoration, this conception lies behind a scripture that is more familiar:
Doctrine and Covenants 130:18-19
18 Whatever principle of intelligence we attain unto in this life, it will rise with us in the resurrection.
19 And if a person gains more knowledge and intelligence in this life through his diligence and obedience than another, he will have so much the advantage in the world to come.
The Doctrine and Covenants teaches this same principle that what we become in this life will directly influence our nature in the next life. This is Alma’s doctrine of restoration, restated. For Alma, it is a restoration because it comes after the transitional period of our death. The Doctrine and Covenants is not focusing on that time between death and resurrection that was so important to Alma (and Corianton) so the perspective of the restoration is not as important as the principle that our current efforts will have meaning in the next life.