The Catholic Church considers its origins to be diabolical and classifies it as a form of paganism.
Pope Eugene IV, Council of Basel, Session 19, Sept. 7, 1434:
“Moreover, we trust that with God’s help another benefit will accrue
to the Christian commonwealth; because from this union, once it is
established, there is hope that very many from the abominable sect of
Mahomet will be converted to the Catholic faith.”
Pope Clement V, Council of Vienne, 1311-1312:
“It is an insult to the holy name and a disgrace to the Christian
faith that in certain parts of the world subject to Christian princes
where Saracens (i.e., The followers of Islam, also called Muslims)
live, sometimes apart, sometimes intermingled with Christians, the
Saracen priests, commonly called Zabazala, in their temples or
mosques, in which the Saracens meet to adore the infidel Mahomet,
loudly invoke and extol his name each day at certain hours from a high
place… This brings disrepute on our faith and gives great scandal to
the faithful. These practices cannot be tolerated without
displeasing the divine majesty. We therefore, with the sacred
council’s approval, strictly forbid such practices henceforth in
Christian lands. We enjoin on Catholic princes, one and all.. They
are to forbid expressly the public invocation of the sacrilegious name
of Mahomet… Those who presume to act otherwise are to be so chastised
by the princes for their irreverence, that others may be deterred from
such boldness.”
St. Thomas Aquinas, Summa Theologica, Pt. II, Q. 12, A. 1, Obj. 2:
“… if anyone were to… worship at the tomb of Mahomet, he would be
deemed an apostate.”
St. Alphonsus, The History of Heresies & Their Refutation, Chap. 7, Article I, On Mahometanism (Islam):
“The impious sect of Mahometanism sprung up in this century [the 7th]…
Mahomet, the founder of this destroying sect… was born in Arabia, in
586… He [Mahomet] pretended to have long conversations with the
Archangel Gabriel, in the cave of Hera… In the year 608, being then
forty years of age, he began to give out that he was a Prophet,
inspired by God, and he persuaded his relatives and domestics of this
first, and then began to publicly preach in Mecca, and attack
idolatry. At first, the people did not very willingly listen to him,
and asked him to prove his mission by a miracle; but he told them that
God sent him to preach the truth, and not to work miracles. The
impostor, however, boasts of having wrought one, though ridiculous in
the extreme: a piece, he says, fell off from the moon into his sleeve,
and he fixed it on again; and it is said that this is the reason for
the Mahometans adopting the half moon as the device of their Empire…
“He composed the Koran… It is a collection of precepts, taken from the Mosaic and Christian Law, together with many of his own, and
interspersed with fables and ridiculous revelations…. He professes
that there is but one God; but in his Alcoran [the Koran] he relates
many trivialities unworthy of the Supreme Being, and the whole work
is, in fact, filled with contradictions, as I have shown in my book on
the ‘Truth of the Faith.’… The Mahometan Paradise, however, is only
fit for beasts; for filthy sensual pleasure is all the believer has to
expect there… The Mahometans shave the head, and leave only a lock of
hair on the crown, by which they hope Mahomet will take them up to
Heaven, even out of Hell itself.”
Pope Callixtus III:
“I vow to… exalt the true Faith, and to extirpate the diabolical sect
of the reprobate and faithless Mahomet [Islam] in the East.”
Pope Pius II from the "Address on the Occasion of the Procession of St. Andrew's Head" April 12, 1462
"Turn the anger of the Almighty against the godless Turks and
Barbarians who despise Christ the Lord.....
Sept 26, 1459 Pope Pius II
In the royal city of the east, they have slain the successor of
Constantine and his people,
desecrated the temples of the Lord, defiled the noble church of
Justinian with their Mohometan abominations. Each success, will only
be a stepping stone until he has mastered all the Western Monarchs,
overthrow the Christian Faith, and imposed the law of his false
prophet on the whole world"
Pope Leo X - Fifth Lateran Council Session 12, Mar 16, 1517
"... the Turks and other infidels ... They treat the way of true light
and salvation with complete contempt and totally unyielding blindness
..."
ope Eugene IV, Council of Basel, 1434:
“… there is hope that very many from the abominable sect of Mahomet
will be converted to the Catholic faith.”
On the Feast of St. Peter and Paul, June 29th 1456 Pope Calixtus III addressed a bull to all bishops, archbishops, patriarchs exhorting them to prayers and added these special directions,
"On the first Sunday of each month, processions were to be made in
every diocese in order to pray that the threatened Turkish invasion
might be averted; the Missae contra Paganos was to be said"
The History of the Popes, from the Close of the Middle Ages - Ludwig Freiherr von Pastor, Frederick Ignatius Antrobus
Also from "A History of the Popes"
On the following day Pius II published a Bull earnestly inviting all
the European Princes to the Congress Since the Emperor Constantine had
given peace to the Church she had never he said been so trampled upon
as she now was by the adherents of the false prophet Mahomet the
bloodthirsty hosts of the venomous dragon It was a punishment from
Heaven for the sins of the nations
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