[W]hat still remains to be said for the Article, In one Holy Catholic Church, on which, though one might say many things, we will speak but briefly.
It is called Catholic then because it extends over all the world, from one end of the earth to the other; and because it teaches universally and completely one and all the doctrines which ought to come to men’s knowledge, concerning things both visible and invisible, heavenly and earthly ; and because it brings into subjection to godliness the whole race of mankind, governors and governed, learned and unlearned; and because it universally treats and heals the whole class of sins, which are committed by soul or body, and possesses in itself every form of virtue which is named, both in deeds and words, and in every kind of spiritual gifts.
In this Holy Catholic Church receiving instruction and behaving ourselves virtuously, we shall attain the kingdom of heaven, and inherit eternal life; for which also we endure all toils, that we may be made partakers thereof from the Lord. For ours is no trifling aim, but our endeavour is for eternal life. (Catechetical Lectures 18.22-23, 28)