"Salvation ONLY in the Catholic Church?"

I'm glad to see that my opponent takes no issue with my self sourcing.I will begin by clarifying 'invincibly ignorant'. As the Catholic Encyclopedia says [1]:'Ignorance is said to be invincible when a person is unable to rid himself of it notwithstanding the employment of moral diligence, that is, such as under the circumstances is, morally speaking, possible and obligatory.'For example, a Native American in the year 50 A.D. would probably be invincibly ignorant of Christ. A Gnostic living in Rome in 70 A.D. would probably not be. Today, very few people are invincibly ignorant, as most people can go on the internet and overcome their ignorance, at which point they stray into the territory of heresy, or rejection of the truth as taught by the Church.Now I will treat with my opponent's arguments.1)a) My opponent claims that Ephesians 2:8-9 proves that faith = salvation.For starters, let's look at Ephesians 2:8-9. What does it actually say? That we are saved by the grace of God, that we cannot work our way to salvation without the grace of God (Pelagianism), and that this is through faith. Certainly, that is true, we cannot save ourselves sine Deo, as it were, but what is a true faith that will save?'(14) What shall it profit, my brethren, if a man say he hath faith, but hath not works? Shall faith be able to save him?(15) And if a brother or sister be naked, and want daily food:(16) And one of you say to them: Go in peace, be ye warmed and filled; yet give them not those things that are necessary for the body, what shall it profit?(17) So faith also, if it have not works, is dead in itself.' - James 2:14-17The point of Ephesians 2:8-9 is not that we are not to do good works, but that we cannot "earn" our salvation by works (we cannot earn salvation by having faith either, salvation is a gift as Ephesians makes quite clear). By doing good works, we cannot then turn to God and say 'Well, I did these good works for you. Pay up, pal! I'll take some eternal happiness for starters.', despite that God will gift us according to our works (cf. Matthew 25, Romans 2:6-8, Revelation 22:12), but this is not because we are owed anything by Him.In fact, if you bother to look at Ephesians 2:10, you see this:'For we are his workmanship, created in Christ Jesus in good works, which God hath prepared that we should walk in them.'b)I'll start out with Matthew 24:12-13'(12) And because iniquity hath abounded, the charity of many shall grow cold.(13) But he that shall persevere to the end, he shall be saved.'It is clear that we are to always avoid sin, and the reason for it is that to fall away at the critical moment, regardless of how vigorously one has fought up until that point, can be enough to doom you (cf. 1 Corinthians 11:12, Matthew 10:22, Mark 13:13).To sin is to fail in your faith (cf. 1 John 3:6), and is therefore to be avoided at all costs.c)That's certainly an odd hypothetical, however ones not dissimilar to it already have been acknowledged.Baptism is a normative necessity, however in an absolutely extreme case it may not be required.While my opponent tries to use the penitent crucified person as an example, that man died under the Old Testament.2)As one Orthodox theologian (close enough, eh?) once said:'We can say where the Church is, but we cannot say where it is not.'3)A person who is not Catholic may be saved, but it is certainly highly unlikely unless they are invincibly ignorant. Thus, a person should be Catholic to obtain salvation.Conclusion:I rest my case.Sources:1. http://www.newadvent.org...;