It’s true that Catholics have heard this message of justification by faith relatively less than Protestants (a lot less, in fact). I think this is because of the natural human tendency (which I’ve often noted) of dichotomizing things and going to extremes in overreaction to opponents. Why this happened in history is obvious:
1) Protestants went too far and adopted faith alone (sola fide), so Catholics — in practice — tended to go too far in the other direction and overemphasize the importance of works and merit (while underemphasizing the true biblical aspects of justification by faith). Some in both camps, in their ignorance, actually taught or practiced Pelagianism or antinomianism.
2) Protestants went too far and adopted Scripture alone (sola Scriptura) as its rule of faith, so Catholics — in practice — tended to go too far in the other direction and overemphasize the importance of Church and Tradition.
Thus, many Protestants have virtually ditched the latter, while many Catholics wouldn’t know the Bible from a hole in the ground (which I have also written about, in a published article; chiding and rebuking my fellow Catholics a bit). Catholics are as ignorant of the Bible as Protestants are ignorant of Church history. Of course, both should be familiar with both. The ignorance on both sides (in different ways) stinks to high heaven. But we can help each other.
3) Protestants (i.e., Luther in his Babylonian Captivity) got radical and radically innovative and threw out five sacraments, so Catholics tended to emphasize the sacraments relatively more than gospel proclamation, evangelization, etc. Of course, in the 16th century, the early Protestants did little missionary work, while Catholics were all over North and South America, so these things ebb and flow.
There are many other similar dichotomies . . .
In my ecumenical emphasis, I like to think that Catholics and Protestants complement each other and “need” each other in this practical, philosophical way, precisely because both sides — in practice — tended to go too far in one direction and to dichotomize what was always intended by God to be together. So we can help each other out a lot, and ecumenism has a crucial function in God’s purposes in the Kingdom.
We can explain to each other our own emphases and try to achieve a consensus insofar as possible and to avoid even more tragic misunderstanding and disunity than we already have.
Hence, my attempts to persuade Protestants that Catholic merit is essentially the same as Lutheran cooperation and sola gratia. I’ve also made many attempts to try to deliberately find common ground. I think it is senseless to wrangle over areas where we essentially agree. There are enough real differences to dispute, heaven knows.
Grace, Faith, Works, & Judgment: A Scriptural Exposition [12-16-09; reformulated & abridged on 3-15-17]