4. Concerning justification:
(a) When that blessed fullness of time had come, the heavenly Father, the Father of mercies, sent Jesus Christ, his own Son, to the human race, in order both to [redeem] the Jews, who were under the law, and to allow the Gentiles, who were not following justice, to attain it, and all people to receive adoption as his children. God sent him forth as a propitiator for our sins through faith in his blood, not for our sins only but also for those of the whole world (Session 6, chapter 2).
(b) Nevertheless, not all people receive the benefit of Christ’s death, but only those with whom he shares the merit earned through his suffering. Therefore if people were not born again in Christ, they never would be justified (Session 6, chapter 3).
(c) The beginning of this justification is to be derived from the preexisting grace of God through Jesus Christ, that is, from his calling to us (Session 6, chapter 5).
(d) We are made ready for his justice when, stirred by divine grace and conceiving faith by hearing, we freely move toward God, believing those things to be true that have been divinely revealed and promised to us — especially this promise, that God justifies the impious by his grace, through the redemption that is in Christ Jesus, and that when we understand that we are sinners and are beneficially struck with fear of divine justice, we are raised to hope since we have confidence that God is appeased toward us because of Christ (Session 6, chapter 6).
(e) This readiness and preparation are followed by the process itself of being justified, which is not only a forgiving of our sins but also a sanctification and renewal of our inner self through the receiving of the grace and of the gifts by which we turn from an unjust person into a just person and from an enemy [of God] into a friend, so that we inherit the hope of everlasting life (Session 6, chapter 7).
(f) The final cause of this justification is the glory of God and of Christ, and life everlasting. The efficient cause is a merciful God who washes and sanctifies us gratuitously. The meritorious cause is God’s most beloved Only-Begotten, our Lord Jesus Christ, who, when we were enemies, for the exceeding goodwill with which he loved us, merited justification for us by his most holy suffering on the wood of the cross, and made satisfaction for us to God the Father. The instrumental cause is the sacrament of baptism, which is the sacrament of the faith without which no one was ever justified. The lone formal cause is the justice of God — not the justice with which he himself is just, but the justice with which he makes us just; namely, the justice with which we, being endowed by him, are renewed in the spirit of our mind, and we are not only reputed just, but are truly called just, and are in fact just, receiving justice within us, each according to our own measure, which the Holy Spirit distributes to everyone as he wills (Session 6, chapter 7, §2).
(g) Justification is a transferal from that state in which we are born a child of the first Adam, to the state of grace and our adoption as children of God through the second Adam, Jesus Christ our Savior (Session 6, chapter 4).