Back in November and early December of 2011, Crisis Magazine ran two articles that address the issue of change in Church teaching. The first, Catholics and “Usury”: A Tragic History, by Jeffrey Tucker, addresses an issue that, at first glance, appears to be largely of historical interest--although the history of that problematic issue ran on for well over a millennium. Usury, of course, is a case in which Church teaching appears rather incontrovertibly to have actually changed, and as such it is cited repeatedly by those who wish the Church to change other teachings, as well. The second article, Can the Church Ban Capital Punishment? by Christopher A. Ferrara, on the other hand, takes up an issue that only arose quite recently. Church teaching on Capital Punishment has not changed--despite some high profile efforts on the part of a recent pontiff--and for some this is a concern. Taken together these articles are an excellent starting point for addressing issues regarding the Church's teaching authority.
