125 Q. When does the Church teach infallibly?  A. The Church teaches infallibly when it speaks through the Pope and bishops united in general council, or through the Pope alone when he proclaims to all the faithful a doctrine of faith or morals.

But how will we know when the Pope speaks ex cathedra, when he is speaking daily to people from all parts of the world?  To speak ex cathedra or infallibly, three things are required: 

(1) He must speak as the head of the whole Church, not as a private person; and in certain forms of words by which we know he is speaking ex cathedra.

(2) What he says must hold good for the whole Church—­that is, for all the faithful, and not merely for this or that particular person or country.

(3) He must speak on matters of faith or morals—­that is, when the Holy Father tells all the faithful that they are to believe a certain thing as a part of their faith; or when he tells them that certain things are sins, they must believe him and avoid what he declares to be sin.  He could not make a mistake in such things.  He could not say that Our Lord taught us to believe and do such and such, if Our Lord did not so teach, because Our Lord promised to be with His Church for all time, and to send the Holy Ghost, who would teach it all truth and abide with it forever.  If then the Church could make mistakes in teaching faith and morals, the Holy Ghost could not be with it, and Our Lord did not tell the truth—­to say which would be blasphemy.  But remember, the Pope is not infallible unless he is teaching faith or morals; that is, what we believe or do in order to save our souls.  If the Holy Father wrote a book on astronomy, mathematics, grammar, or even theology, he could make mistakes as other men do, because the Holy Ghost has not promised to guide him in such things.  Nevertheless, whatever the Pope teaches on anything you may be pretty sure is right.  The Pope is nearly always a very learned man of many years’ experience.  He has with him at Rome learned men from every part of the world, so that we may say he has the experience of the whole world.  Other rulers cannot and need not know as much as the Holy Father, because they have not to govern the world, but only their own country.  Moreover, there is no government in the whole world as old as the Church, no nation that can show as many rulers without change; so we may say the Pope has also the experience of all the Popes who preceded him, from St. Peter down to our present Holy Father, Pius XI—­two hundred and sixty-one popes.  Therefore, considering all this, we should have the very greatest respect for the opinions and advice of the Holy Father on any subject.  We should not set up our limited knowledge and experience against his, even if we think that we know better than he does about certain political events taking place in our country, for we are not sure that we do.  The Holy Father knows the past history of nations; he