§ 1807 Justice is the moral virtue that consists in the constant and firm will to give their due to God and neighbor. Justice toward God is called the “virtue of religion.” Justice toward men disposes one to respect the rights of each and to establish in human relationships the harmony that promotes equity with regard to persons and to the common good. The just man, often mentioned in the Sacred Scriptures, is distinguished by habitual right thinking and the uprightness of his conduct toward his neighbor. You shall not be partial to the poor or defer to the great, but in righteousness shall you judge your neighbor. “Masters, treat your slaves justly and fairly, knowing that you also have a Master in heaven.”
Had Adam not sinned, original justice would have been transmitted to all his descendants. The Fall of Adam immediately replaced the state of original justice with the state of original sin which instead was transmitted to all of Adam’s descendants.
§ 374 The first man was not only created good, but was also established in friendship with his Creator and in harmony with himself and with the creation around him, in a state that would be surpassed only by the glory of the new creation in Christ.
§ 375 The Church, interpreting the symbolism of biblical language in an authentic way, in the light of the New Testament and Tradition, teaches that our first parents, Adam and Eve, were constituted in an original state of holiness and justice. This grace of original holiness was to share in divine life.
§ 376 By the radiance of this grace all dimensions of man’s life were confirmed. As long as he remained in the divine intimacy, man would not have to suffer or die. The inner harmony of the human person, the harmony between man and woman, and finally the harmony between the first couple and all creation, comprised the state called original justice.
§ 377 The mastery over the world that God offered man from the beginning was realized above all within man himself: mastery of self. The first man was unimpaired and ordered in his whole being because he was free from the triple concupiscence that subjugates him to the pleasures of the senses, covetousness for earthly goods, and self-assertion, contrary to the dictates of reason.
§ 378 The sign of man’s familiarity with God is that God places him in the garden. There he lives to till it and keep it. Work is not yet a burden, but rather the collaboration of man and woman with God in perfecting the visible creation.
§ 379 This entire harmony of original justice, foreseen for man in God’s plan, will be lost by the sin of our first parents.