Shedd:
"But the Council of Trent resolved justification into sanctification, and in the place of a gratuitous justification and remission of sins through the expiation of the Redeemer, substituted the most subtle form of the doctrine of justification by works that has yet appeared, or that can appear. For the doctors of Trent do not teach, in their canonical statements, that man is justified and accepted at the bar of justice by his external acts of obedience to the moral or the ecclesiastical law. This is, indeed, the doctrine that prevails in the common practice of the Papal Church, but it is not the form in which it appears in the Tridentine canons. According to these, man is justified by an inward and spiritual act which is denominated (editors: called) the act of faith; by a truly divine and holy habit or principle infused by the gracious working of the Holy Spirit.
The ground of the sinner's justification (ed.: according to Trent) is thus a divine and gracious one. God works in the sinful soul to will and to do, and by making it inherently just justifies it. And all this is accomplished through the merits and mediation of Jesus Christ; so that, in justification there is a combination of the objective work of Christ with the subjective character of the believer. This statement is the more subtle, because it distinctly refers the infused grace or holiness to God as the author, and thereby seems to preclude the notion of self-righteousness. But it is fundamentally erroneous, because this infused righteousness, or holiness of heart, upon which remission of sins rests in part, is not piaculor (propitiatory). It has in it nothing of the nature of a satisfaction to justice.2 So far forth, therefore, as infused grace in the heart is made a ground and procuring cause of the pardon of sin, the judicial aspects and relations of sin are overlooked, and man is received into the Divine favor without any true and proper expiation of his guilt. The Papal theory of justification, consequently, stands upon the same level in the last analysis with the Socinian, or with any theory that denies the necessity of a satisfaction of justice."