Q. 519.  How do we know that the Church must have the four marks and three attributes usually ascribed or given to it?  A. We know that the Church must have the four marks and three attributes usually ascribed or given to it from the words of Christ given in the Holy Scripture and in the teaching of the Church from its beginning.

Q. 520.  Can the Church have the four marks without the three attributes?  A. The Church cannot have the four marks without the three attributes, because the three attributes necessarily come with the marks and without them the marks could not exist.

Q. 521.  Why are both marks and attributes necessary in the Church?  A. Both marks and attributes are necessary in the Church, for the marks teach us its external or visible qualities, while the attributes teach us its internal or invisible qualities.  It is easier to discover the marks than the attributes; for it is easier to see that the Church is one than that it is infallible.

Q. 522. {122} Which are the attributes of the Church?  A. The attributes of the Church are three:  authority, infallibility, and indefectibility.

Q. 523.  What is authority?  A. Authority is the power which one person has over another so as to be able to justly exact obedience.  Rulers have authority over their subjects, parents over their children, and teachers over their scholars.

Q. 524.  From whom must all persons derive whatever lawful authority they possess?  A. All persons must derive whatever lawful authority they possess from God Himself, from whom they receive it directly or indirectly.  Therefore, to disobey our lawful superiors is to disobey God Himself, and hence such disobedience is always sinful.

Q. 525. {123} What do you mean by the authority of the Church?  A. By the authority of the Church I mean the right and power which the Pope and the Bishops, as the successors of the Apostles, have to teach and to govern the faithful.

Q. 526. {124} What do you mean by the infallibility of the Church?  A. By the infallibility of the Church I mean that the Church can not err when it teaches a doctrine of faith or morals.

Q. 527.  What do we mean by a “doctrine of faith or morals”?  A. By a doctrine of faith or morals we mean the revealed teaching that refers to whatever we must believe and do in order to be saved.

Q. 528.  How do you know that the Church can not err?  A. I know that the Church can not err because Christ promised that the Holy Ghost would remain with it forever and save it from error.  If, therefore, the Church has erred, the Holy Ghost must have abandoned it and Christ has failed to keep His promise, which is a thing impossible.

Q. 529.  Since the Church can not err, could it ever be reformed in its teaching of faith or morals?  A. Since the Church can not err, it could never be reformed in its teaching of faith or morals.  Those who say the Church needed reformation in faith or morals accuse Our Lord of falsehood and deception.