Chapter 11 — Part I: The Creed — Article IX: The Holy Catholic Church; the Communion of Saints
Section 21. Those Who Are Not Members Of The Church — Hence there are but three classes of persons excluded from the Church's pale: infidels, heretics and schismatics, and excommunicated persons. Infidels are outside the Church because they never belonged to, and never knew the Church, and were never made partakers of any of her Sacraments. Heretics and schismatics are excluded from the Church, because they have separated from her and belong to her only as deserters belong to the army from which they have deserted. It is not, however, to be denied that they are still subject to the jurisdiction of the Church, inasmuch as they may be called before her tribunals, punished and anathematised. Finally, excommunicated persons are not members of the Church, because they have been cut off by her sentence from the number of her children and belong not to her communion until they repent.