An important part of the theologians' task is to make the church's dogmas meaningful to the faithful of their own time. The attitude with which a theologian should undertake this task of communicating a contemporary understanding of the faith is well described as one of creative fidelity. Two basic sources for Catholic theology are scripture and the documents of the Magisterium. Just as Catholic theologians must know how to distinguish among the various literary genres in the bible and how to interpret scriptural texts, they must also know how to determine the relative degree of authority exercised in the various documents issued by popes or councils and how to apply the principles of hermeneutics in interpreting them. This book offers guidelines that will help those interested in Catholic theology to make sound judgments about the authority and meaning of the documents in which the church has expressed its faith over the centuries. Making such judgments requires a knowledge of the correct level of response these documents call for from the faithful and the ability to offer to today's faithful a contemporary understanding of their faith. The task of the interpreter is one of creative fidelity, requiring a delicate balance between being faithful to the original meaning of the text and creative in finding the concepts and terms that make it meaningful today.
Frank Sullivan's book is simply a must-read and know book for anyone who reads an official Catholic Church document, EVER! Fr. Sullivan does a thorough job of explaining what dogma is, how it is different from doctrine, and the principles that one must consider - questions being asked, history of development around the issue, purpose of the teaching - when evaluating whether something is a dogma, a definitive doctrine, a non-definitive doctrine, or a theological opinion. He develops key interpretive principles for weighing the importance of text and provides ample examples from ancient and more recent church history. I find this book to be extremely helpful to combat "armchair" church experts who think that everything the popes say is infallible and who do not understand that an ecumenical council's writings (like those of Vatican II) matter more doctrinally than a memo from the Roman Curia. These distinctions and more enable people to read the official teaching texts of the church more comprehensively, and more faithfully. Fr. Sullivan also points out the creative role of theologians in finding the best ways to express doctrines in ways that make sense in contemporary language, though this book would be better if he offered a bit more on this point.
I can see why Michael Lofton of Reason and Theology holds Fr. Sullivan in such high regard. In this work, Fr. Sullivan does a good job of outlining the different levels of magisterial authority and evaluating defined dogmas proclaimed in all the Church's ecumenical councils, which he presents in the beggining chapters of Creative Fidelity. However, I must caution those who wish to read Fr. Sullivan's work, as he seems to be extremely critical of undefined dogmas within the Ordinary and Universal Magisterium. He seems to think that disagreement on a matter by a minority of contemporary theologians can subvert the principle of "unanimous teaching of the whole [Church]" when determining if a teaching has been infallibly taught by the Ordinary and Universal Magisterium. This occurs most notably on his stances regarding contraception, the immorality of abortion and euthanasia, and the exclusive ordination of men. His opinions become even more problematic in light of the theologian's duty to refrain from public disagreement on matters definitively stated by the Ordinary Magisterium in Donum Veritatis. Alongside this, although he cites St. John Henry Newman with regard to the lack of infallibility in the Syllabus of Errors, he fails to cite Newman's acceptance of the infallible condemnations in Quanta cura (from which the Syllabus of Errors derives). Fr. Sullivan also cites Fr. Karl Rahner more than I would feel comfortable relying upon.
I would only recommend reading this if you already have a decent understanding of the Magisterium, the distinction between infallible and authoritative non-infallible teachings, whether teachings of the Church can change, etc.