Trent, Justification, and lack of Precedence
At the Council of Trent, beginning in 1545, the condemnation of the Protestant schism as a whole may have been a foregone conclusion, but it was still by no means obvious which aspects of the doctrine of justification would be condemned and which might yet be assimilated. In part, the difficulty was caused by the absence of an authoritative katholische Rechtfertigungslehre [catholic statement on justification] against which to measure the reformatische [Reformation].
David Fink, Divided by Faith: The Protestant Doctrine of Justification and the Confessionalization of Biblical Exegesis (Durham, NC: Duke University, 2012), 25