The justification of an adult human being does not take place suddenly, but runs through certain well-defined stages, which in their totality are called the process of justification.

Being a "regeneration in God," justification bears a striking resemblance to the development of the foetus in the maternal womb. Like physical birth, spiritual regeneration is preceded by travailing, i.e. fear and painful contrition.

The dogmatic teaching of the Catholic Church on justification is formally defined by the Tridentine Council, whose decrees(780) contain a masterly analysis of this most interesting of psychological processes. The holy Synod puts faith at the beginning. "Faith," it says, "is the beginning of human salvation, the foundation and the root of all justification."(781) The nature of faith and the part it plays in justification were the chief points in dispute between the Church and the so-called Reformers. Luther and his followers denatured the traditional Catholic teaching by basing justification solely on faith, which they falsely defined as mere confidence or trust in the mercy of God.