St. Bernard is another theologian who demonstrates that there was not a 700 year unanimous opinion on the subject.
St. Bernard of Clairvaux (Doctor of the Church) – 1090-1153 AD
Letter No.77, Letter to Hugh of St. Victor, On Baptism:
§6. If an adult...wish and seek to be baptized, but is unable to obtain it because death intervenes, then where there is no lack of right faith, devout hope, sincere charity, may God be gracious to me, because I cannot completely despair of salvation for such a one solely on account of water, if it be lacking, and cannot believe that faith will be rendered empty, hope confounded and charity lost, provided only that he is not contemptuous of the water, but as I said merely kept from it by lack of opportunity... §7. But I am very much astonished if this new inventor of new assertions and assertor of inventions has been able to find in this matter arguments which escaped the notice of the holy fathers Ambrose and Augustine or an authority greater than their authority. [He then quotes both passages given above...] §8. Believe me, it will be difficult to separate me from these two columns, by which I refer to Augustine and Ambrose...believing with them that people can be saved by faith alone and the desire to receive the sacrament, however only in the case that un timely death or some other insuperable force keep them from fulfilling their pious desire. Notice also that, when the Savior said “whoever believes and is baptized will be saved,” He cautiously and alertly did not repeat the phrase “who was not baptized,” but only “whoever does not believe will be condemned” (Mk. 16:16). This intimated that sometimes faith alone would suffice for salvation, and that without it, nothing would be sufficient.
For this reason, even if it is granted that martyrdom can take the place of baptism, it is clearly not the penalty which does this, but faith itself. For without faith what is martyrdom, if not a penalty? It is faith's doing that martyrdom can without any doubt be considered the equivalent of baptism. Would not faith be very sickly and weak in itself, if what it can give to another, it cannot obtain by itself? To be sure, to pour out one's blood for Christ is an indubitable proof of great faith–but to men, not to God. But what if God, who needs to perform no experiments to test for what He wants, saw great faith in the heart of someone dying in peace, not put to the question by martyrdom, but suitable for martyrdom nevertheless? If he remembers that he has not yet received the sacrament and sorrowfully and repentantly asks for it with all his heart, but cannot receive it because his death comes too quickly, will God damn his faithful one? Will He damn, I ask, a person who is even prepared to die for Him? Paul says: “No one can say Jesus is Lord, except in the Holy Ghost” (I Cor. 12:3).
Will we say that such a one, who at the moment of death not only invokes the Lord Jesus, but asks for the sacrament with his every longing, either does not speak in the Holy Ghost, so that the Apostle was mistaken, or is damned even though he has the Holy Ghost? He has the Savior dwelling in his heart by faith (Eph 3:17) and in his mouth by confession (Rom 10:10); will he then be damned with the Savior? Certainly if martyrdom obtains its prerogative only by the merit of faith, so that it is safely and singularly accepted in the place of baptism, I do not see why faith itself cannot with equal cause and without martyrdom be just as great in God's eyes, who knows of it without the proof of martyrdom. I would say it can be just as great as far as obtaining salvation goes, but it is not as great in regard to the accuмulation of merit, in which martyrdom surely surpasses it. We read: “Everyone who hates his brother is a murderer” (I Jn. 3:15); and again, “Whoever looks at a woman lustfully has already committed adultery with her in his heart” (Mt. 5:28). How could it be more evident that the wish is considered the equivalent of the deed, when necessity excludes the deed? That is, unless one thinks that God, who is love, would impute us the evil deeds of the will and not the good, and that the merciful and compassionate Lord is more ready to punish than to reward. Suppose someone who is at the point of death happens to remember that he is bound by a debt to another. If he lacks the means to pay it, he is still believed to obtain pardon solely by repentance and contrition of heart, and so he is not damned on account of it. In the same way, faith alone and turning the mind to God, without the spilling of blood or the pouring of water, doubtlessly bring salvation to one who has the will but not the way– because death intervenes–to be baptized. And just as in the former case no repentance remits sin if, when he can, he does not restore what he owes, so in the latter faith is of no avail, if, when he can, he does not receive the sacrament. He is shown not to have perfect faith, if he neglects to do so. True and full faith complies with all the commandments; this particular commandment is the foremost of them all.