Schaf says that one of the objections Roman Catholics have (or had) with the doctrine of justification by faith alone is that it involves God’s “declaring a man to be what he is not in fact.” Schaf goes on to point out that this is not so absurd since there are several instances of this very thing in Scripture. God loved us even while we were still sinners not for something he saw already in them, but for that which he intended them. Likewise, Abraham was called the father of many nations before he actually was.
But Schaf goes further and says that the Reformed “always acknowledged the true element here in the catholic doctrine, without sanctioning its pelagianistic trait.” Thus, Schaf insists that God is not merely making a lone, abstract judgment that is unrelated to reality. On the contrary, the declaration of righteousness rests upon the objective union with Christ that exists, the “actualization of this principle in his person, is itself conditioned by the declaratory act, creative at the same time, going before.” In other words, simultaneous to the declaration of righteousness is the creative union of the believer with the risen Christ, thereby enacting and performing the reality of the declaration.
(The Principle of Protestantism, 67-69)