Taylor,

Thanks for your question.

The gift of infallibility prevents the Church from teaching error in area of faith and morals.

An index of forbidden books is not a teaching. It's the implementation of a discipline. The Church for pastoral reasons banned certain books during the Reformation. That might seem a bit extreme today but we have to look at the historical context. At the time, the Church was concerned with preserving the orthodoxy of the laity.

At the time, the laity did not have access to all theological works, much like they do today. Moreover, the laity was mostly illiterate. The point is, that the Reformers, with the advent of the printing press, were publishing heretical writings at a great pace. These books were being distributed and read to Catholic laity, exposing them to heresy. The same laity did not have the benefit of being able to read authentic Catholic Teaching, because it had yet to be published in mass, like the heresies being promulgated by the Reformers.

The Church's solution was to ban the reading of heretical works. This was temporary solution, that perhaps lasted too long, but I wouldn't be to quick to pass judgment on the Church's decision.

The gift of infallibility doesn't really come into play here. The Church certainly had, and still has, the authority to impose a discipline on the faithful. That doesn't mean that the discipline is the same as an infallible matter of faith and morals.

In short, The Church can infallibly discern doctrine. In so doing, She infallibly identifies heresy. Whether or not the Church decides to allow the faithful to read the heresy, is a discipline which is not protected by the gift of infallibility. The faithful nevertheless are obliged to obey the discipline in humility, recognizing that Holy Mother Church has been given the authority to impose disciplines for the benefit of the faithful.

I hope this helps,

John D.
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