The Extraordinary Synod on the Family that just concluded has prompted me to reread Judge John T. Noonan's wonderful book A Church That Can and Cannot Change. Here's the gist, as summarized by Amazon:
Using concrete examples, John T. Noonan, Jr., demonstrates that the moral teaching of the Catholic Church has changed and continues to change without abandoning its foundational commitment to the Gospel of Jesus Christ.
Specifically, Noonan looks at the profound changes that have occurred over the centuries in Catholic moral teaching on freedom of conscience, lending for a profit, and slavery. He also offers a close examination of the change now in progress concerning divorce.
In these changes, Noonan perceives the Catholic Church to be a vigorous, living organism, answering new questions with new answers, and enlarging the capacity of believers to learn through experience and empathy what love demands. He contends that the impetus to change comes from a variety of sources, including prayer, meditation on Scripture, new theological insights and analyses, the evolution of human institutions, and the examples and instruction given by persons of good will.
Noonan also states that the Church cannot change its commitment to preaching the Gospel of Jesus Christ. Given this absolute, how can the moral teaching of the Church change? Noonan finds this question unanswerable when asked in the abstract. But in the context of the specific facts and events he discusses in this book, an answer becomes clear. As our capacity to grasp the Gospel grows, so too, our understanding and compassion, which give life to the Gospel commandments of love, grow.
Noonan is a brilliant judge and lawyer and deploys his considerable skills as an advocate to great effect here. But he's not neutral. He has an axe to grind and does so at length. So while I recommend it very highly, I also recommend reading some of his critics. Avery Cardinal Dulle's review at First Things would be a good place to start. After reviewing each of the doctrines Noonan claims have evolved, Dulles concludes that:
Noonan has written a stimulating book dealing with questions of great importance. He shows himself to be knowledgeable about the history of the four problems here treated. He brings to bear many of the skills of a historian, a civil lawyer, a canon lawyer, and to some degree those of a theologian. Anyone who wishes to question Noonan’s conclusions must at least take account of the facts he has unearthed. He renders no small service in presenting the most powerful objections against continuity that can be raised.
The reader should be warned, however, that Noonan manipulates the evidence to make it seem to favor his own preconceived conclusions. For some reason, he is intent on finding discontinuity” but he fails to establish that the Church has reversed her teaching in any of the four areas he examines.
Arthur Hippler's review would also reward study.
Lastly, one might ponder Cardinal Dolan's recent observation that:
A synod by its nature can hardly change the Church’s teaching. We Catholics pledge allegiance to what is called a “revealed religion” (so do Jews, other Christians, and Moslems). That simply means that we believe that God has told us (“revealed”) certain things about Himself and ourselves through the Bible, through our own nature, especially through His Son, all celebrated and taught by His Church. ...
Anyone who thought this synod could change that has not read Catholicism for Dummies. The Church does not change God’s revelation, but attempts to change us so we can live it.
Does Church teaching evolve? Adapt? It's an important and fascinating debate. Noonan and his critics provide plenty of food for thought.