Muslims go to hell.

The Life of St. Francis Xavier Apostle of the Indies and Japan By Daniello Bartoli, J. P. Maffei, Frederick William Faber: "

"He particularly regretted the loss of two Moorish (Muslim) slaves who were in the skiff, because the loss of temporal life would lead them to eternal death."

Victories of the Martyrs (by St. Alphonsus de Liguori):

St. George.

July 27.

SPAIN was honored by the martyrdom of many Christians under the Moors, in the ninth century. Among these was Aurelius, who was born in Corduba, of an opulent and noble family. His father was a Mahomedan, and his mother a Christian; but having been left an orphan very young, he was reared by his aunt in the Christian religion. The Mahomedan books which the Moors made him read served only to convince him of the falsity of their sect, and to make him more enamoured of the religion of Jesus Christ. Urged by his relatives to marry, he espoused Natalia, a Christian virgin, remark able for her piety.

...

The holy monk answered: "Meanwhile, sister, I have earned this much for Christ;" and having raised himself up very much bruised, he was in that state presented with the rest to the governor, who asked them why they thus blindly ran to death, and made them promises of the most ample rewards if they would renounce Jesus Christ. They answered with one accord: "These promises can avail nothing. We despise this present life, because we hope for a better one. We love our faith, and abhor every other religion." Hereupon the governor sent them to prison, and having found them constant in their faith at the end of five days, condemned them all to death, with the exception of George. But the holy monk having declared that Mahomet was a disciple of the devil, and that his followers were in a state of perdition, he also was condemned with his companions.

St. Alphonsus and EENS

p. 456-457 of The History of Heresies and Their Refutation:

10. They [Semipelagians] object, fourthly, and say: If even for the beginning of Faith preventing grace is necessary, then the infidels, who do not believe, are excusable, because the Gospel was never preached to them, and they, therefore, never refused to hear it. Jansenius (9) says that these are not excused, but are condemned, without having had any sufficient grace, either proximate or remote, to become converted to the faith, and that is, he says, in punishment of original sin, which has deprived them of all help. And those theologians, he says, who in general teach that these infidels have sufficient grace for salvation, some way or other have adopted this opinion from the Semipelagians. This sentiment of Jansenius, however, is not in accordance with the Scripture, which says that God " will have all men to be saved, and come to the knowledge of the truth" (1 Tim. ii. 4); " He was the true light, which enlighteneth every man that cometh into the world" (John, i. 9); " Who is the Saviour of all men, especially the faithful" (1 Tim. iv. 10); " And he is the propitiation for our sins, and not for ours only, but also for those of the whole world''(1 John, ii. 2); "Who gave himself a redemption for all" (1 Tim. ii. 6). From these texts Bellarmin (10) remarks, that St. Chrysostom, St. Augustin, and St. Prosper conclude that God never fails to give to all men sufficient assistance to work out their salvation, if they desire it. And St. Augustin (11), especially, and St. Prosper (12), express this doctrine in several parts of their works. Besides, this sentiment of Jansenius is in direct opposition to the condemnation pronounced by Alexander VIII., in 1690, on that proposition, that Pagans, Jews, &c., have no sufficient grace: " Pagani, Judxi, Haeretici, aliique hujus generis nulluru omnino accipiunt a Jesu Christo influxum: adeoque hinc recte inferes, in illis esse voluntatem nudam et inermem sine omni gratia sufficiente." Neither does it agree with the condemnation pronounced by Clement XI. on two propositions of Quesnel (26, 29): " That there are no graces unless by Faith," and that "no grace is granted outside the Church."

Still we answer the Semipelagians, and say, that infidels who arrive at the use of reason, and are not converted to the Faith, cannot be excused, because though they do not receive sufficient proximate grace, still they are not deprived of remote grace, as a means of becoming converted. But what is this remote grace? St. Thomas explains it, when he says, that if anyone was brought up in the wilds, or even among brute beasts, and if he followed the law of natural reason, to desire what is good, and to avoid what is wicked, we should certainly believe either that God, by an internal inspiration, would reveal to him what he should believe, or would send someone to preach the Faith to him, as he sent Peter to Cornelius. Thus, then, according to the Angelic Doctor [St. Thomas], God, at least remotely, gives to infidels, who have the use of reason, sufficient grace to obtain salvation, and this grace consists in a certain instruction of the mind, and in a movement of the will, to observe the natural law; and if the infidel cooperates with this movement, observing the precepts of the law of nature, and abstaining from grievous sins, he will certainly receive, through the merits of Jesus Christ, the grace proximately sufficient to embrace the Faith, and save his soul.”

Pg. 634 - 635 The History of Heresies, and Their Refutation:

The devil always strives to deceive heretics, by suggesting to them that they can be saved in their belief. This was what Theodore Beza said to St. Francis de Sales, when hard pressed by him on the importance of salvation: "I hope to be saved in my own religion." Unhappy hope! which only keeps them in error here, and exposes them to eternal perdition hereafter, when the error cannot be remedied. I think the danger of eternal perdition, by dying separated from the Church, should be a sufficient motive to convert every heretic. It was this that made Henry IV. forsake Calvinism, and become a Catholic. He assembled a conference of Catholics and Calvinists, and after listening for a time to their arguments, he asked the Calvinistic doctors if it was possible a person could be saved in the Catholic faith; they answered that it was; "Then," said the King, " if the faith of the Roman Church secures salvation, and the Reformed faith is at least doubtful, I will take the safe side and become a Catholic."

All the misfortunes of unbelievers spring from too great an attachment to the things of this life. This sickness of heart weakens and darkens the understanding, and leads many to eternal ruin. If they would try to heal their hearts by purging them of their vices, they would soon receive light, which would show them the necessity of joining the Catholic Church, where alone is salvation. My dear Catholics, let us thank the Divine goodness, who, among so many infidels and heretics, has given us the grace to be born and live in the bosom of the Holy Roman Catholic Church, and let us take heed and not be ungrateful for so great a benefit. Let us take care and correspond to the Divine grace, for if we should be lost (which God forbid), this very benefit of grace conferred on us would be one of our greatest torments in hell.

St. Leonard and EENS

St. Leonard of Port Maurice's sermon "On the Little Number of Those Who are Saved":

"Brothers, you must know that the most ancient belief is the Law of God, and that we all bear it written in our hearts; that it can be learned without any teacher, and that it suffices to have the light of reason in order to know all the precepts of that Law. That is why even the barbarians hid when they committed sin, because they knew they were doing wrong; and they are damned for not having observed the natural law written in their heart: for had they observed it, God would have made a miracle rather than let them be damned; He would have sent them someone to teach them and would have given them other aids, of which they made themselves unworthy by not living in conformity with the inspirations of their own conscience, which never failed to warn them of the good they should do and the evil they should avoid. So it is their conscience that accused them at the Tribunal of God, and it tells them constantly in hell, "Thy damnation comes from thee." They do not know what to answer and are obliged to confess that they are deserving of their fate.

Now if these infidels have no excuse, will there be any for a Catholic who had so many sacraments, so many sermons, so many aids at his disposal? How will he dare to say, "If God was going to damn me, then why did He create me?" How will he dare to speak in this manner, when God gives him so many aids to be saved? So let us finish confounding him.

You who are suffering in the abyss, answer me! Are there any Catholics among you? "There certainly are!" How many? Let one of them come here! "That is impossible, they are too far down, and to have them come up would turn all of hell upside down; it would be easier to stop one of them as he is falling in." So then, I am speaking to you who live in the habit of mortal sin, in hatred, in the mire of the vice of impurity, and who are getting closer to hell each day. Stop, and turn around; it is Jesus who calls you and who, with His wounds, as with so many eloquent voices, cries to you, "My son, if you are damned, you have only yourself to blame: Thy damnation comes from thee.' Lift up your eyes and see all the graces with which I have enriched you to insure your eternal salvation. I could have had you born in a forest in Barbary; that is what I did to many others, but I had you born in the Catholic Faith; I had you raised by such a good father, such an excellent mother, with the purest instructions and teachings. If you are damned in spite of that, whose fault will it be? Your own, My son, your own: "Thy damnation comes from thee.'

St. Jean-Marie-Baptiste Vianney and EENS

The Curé of Ars had an interview one day with a rich Protestant. The servant of God did not know that he had the misfortune to belong to a sect, and spoke to him, as he was accustomed to do, of our Lord and the saints with the warmest effusion, ending by putting a medal into his hand. The other said, on receiving it:

"M. le Curé, you are giving a medal to a heretic — at least, I am a heretic only from your point of view. Notwithstanding the difference of our belief, I hope we shall both be one day in heaven."

The good Curé took his hand, and fixing on him his eyes, which expressed his lively faith and his burning charity, he said, in a tone of deep compassion and tenderness: "Alas, my friend, we shall be united above only inasmuch as we have begun to be so upon earth; death will make no change. Where the tree falls, there it lies."

"M. le Curé, I trust in Christ, who said, 'He who believeth in Me shall have eternal life.'"

"Ah! my friend, our Lord also said other things. He said that whoever would not listen to the Church should be regarded as a heathen. He said that there was to be but one flock and one shepherd, and He appointed St. Peter to be the head of that flock." Then, speaking in a more gentle and insinuating voice, "My friend, there are not two ways of serving our Lord — there is only one good way; and it is to serve Him as He wishes to be served." Thereupon the good Curé disappeared, leaving that man penetrated with a salutary uneasiness, the forerunner of divine grace, by which he was afterwards happily overcome.

http://books.google.com/books?id=-QEDAAAAQAAJ&pg=PA168&dq=I+am+a+heretic+from+your+point+of+view.+vianney&as_brr=1