The three articles by Fr. Gallitzin included here were originally published in sequence over a period of several years. The first, A Defense of Catholic Principles, was published in response to a public sermon of a protestant clergyman who used the occasion to attack the Church. The second, An Appeal to the Protestant Public, was published after the clergyman responded with a public “Vindication” of his remarks and accusations, which utterly failed to address Gallitzin’s Defense. One of the results of this exchange was that a friendship developed between Gallitzin and another protestant minister who eventually converted. It became clear to Gallitzin that any attempt to convince protestants of the truths of the Faith must depend for its effectiveness, not upon appeals to authority or tradition, but rather to scripture. This he did in his Letter to a Protestant Friend on the Holy Scriptures. All three articles are masterful, manly, and effective. Many protestants converted. We are pleased to make these writings available to a new generation of Catholic evangelists.