You are not right in the head.

The holy synod especially condemns and censures, in the book, the assertion which is scandalous, erroneous in the faith and offensive to the ears of the pious faithful, namely: Christ sins daily and has sinned daily from his very beginning, even though he avers that he does not understand this as of Christ our saviour, head of the church, but as referring to his members, which together with Christ the head form the one Christ, as he asserts. Also, the propositions, and ones similar to them, which the synod declares are contained in the articles condemned at the sacred council of Constance, namely the following. Not all the justified faithful are members of Christ, but only the elect, who finally will reign with Christ for ever. The members of Christ, from whom the church is constituted, are taken according to the ineffable foreknowledge of God; and the church is constituted only from those who are called according to his purpose of election. To be a member of Christ, it is not enough to be united with him in the bond of charity, some other union is needed. Also the following. The human nature in Christ is really Christ. The human nature in Christ is the person of Christ. The intimate cause that determines the human nature in Christ is not really distinguished from the nature that is determined. The human nature in Christ is without doubt the person of the Word; and the Word in Christ, once the nature has been assumed, is really the person who assumes. The human nature assumed by the Word in a personal union is truly God, natural and proper. Christ according to his created will loves the human nature united to the person of the Word as much as he loves the divine nature. Just as two persons in God are equally lovable, so the two natures in Christ, the human and the divine, are equally lovable on account of the common person. The soul of Christ sees God as clearly and intensely as God sees himself.

I'm still at a loss here.  Every Catholic believes that the dogma of the Holy Trinity was taught from the very beginning of the Church by the Apostles.  If at a later time additional clarifications were made by the Magisterium (in condemning various erroneous VIEWS of the Holy Trinity), that doesn't mean that early Christians had no explicit faith in the Holy Trinity.  You're gravely mistaken on this point.

"It is impossible to believe explicitly in the mystery of Christ, without faith in the Trinity, since the mystery of Christ includes that the Son of God took flesh; that He renewed the world through the grace of the Holy Ghost; and again, that He was conceived by the Holy Ghost.  Wherefore just as, before Christ, the mystery of Christ was believed explicitly by the learned, but implicitly and under a veil, so to speak, by the simple, so too was it with the mystery of the Trinity.  And consequently, when once grace had been revealed, all were bound to explicit faith in the mystery of the Trinity: and all who are born again in Christ, have this bestowed on them by the invocation of the Trinity, according to Matthew 28:19: 'Going therefore teach ye all nations, baptizing them in the name of the Father, and of the Son and of the Holy Ghost.'" (Summa Theologica, IIa IIae, q.2, a.8)

On the Day of Pentecost, numerous pagans who had implicit faith in Christ fell from grace without their knowledge and/or consent.

One is not bound to believe in the mysteries of the Incarnation and the Blessed Trinity but only "once grace had been revealed."  It is a necessity of precept as opposed to a necessity of means.  What you are trying to argue is that explicit faith in the mysteries of the Incarnation and Blessed Trinity are a necessity of means

If a person is united to Christ through "the bonds of charity," then the Council of Florence is, clearly, saying that "no other union is needed", which means that love, hence, obedience, to the commands of God are all that is needed for a person to be united to Christ, who is God, and hence, His Mystical Body, which is the Catholic Church.   Therefore, if a person, through no fault of his own, is simply ignorant of the commands of Christ (namely, to be baptized and submit himself/herself to the Roman Pontiff), then such a person could be in a state of grace through his/her implicit desire to receive the Sacraments, out of their love for God, who is Christ.  That is what the Council of Florence is teaching.

Quote from: Jehanne

One is not bound to believe in the mysteries of the Incarnation and the Blessed Trinity but only "once grace had been revealed."  It is a necessity of precept as opposed to a necessity of means.  What you are trying to argue is that explicit faith in the mysteries of the Incarnation and Blessed Trinity are a necessity of means

No, knowledge of these mysteries required as the matter for suprenatural faith, as per the Vatican I quote; theologians who hold that explicit belief in the Trinity and Incarnation are required for salvation do not teach that this is by necessity of precept only.  Otherwise, this position becomes completely meaningless ... as you are desperately trying to make it.

The subject of the salvation of sincere non-Catholics was on the agenda of the Vatican Council. For this purpose the two docuмents of Pius IX on invincible ignorance were quoted in extenso and the essential terms were fully explained. “By the words, ‘those who labor in invincible ignorance’ is indicated the possibility that a person may not belong to the visible and external communion of the Church, and yet may attain to justification and eternal life.” [25] Moreover the saving clause on invincibility was incorporated into a proposed definition, namely, “It is a dogma of faith that no one can be saved outside the Church. However, those who labor in invincible ignorance of Christ and His Church are not to be punished for this ignorance with eternal pains, since they are not burdened with guilt on this account in the eyes of God, who wishes all men to be saved and to come to the knowledge of the truth, and who does not deny His grace to the person who does what he can, to enable him to attain to justification and eternal life. But this salvation no one attains, who leaves this life culpably separated from the unity of faith and communion of the Church.” [26] Consequently, although the doctrine of Pius IX remained part of the unfinished business of the Vatican Council and was not formally defined, it is certainly definable and may be called proxima fidei or “practically of faith.”

However, the council did manage to express itself more directly on the subject in another context. The final draft of the Constitution on the Faith (infallibly defined) includes two successive statements. First an exposition of the object of faith, that “by divine and Catholic faith all those things must be believed which are contained in the word of God, written or handed down, and which are proposed by the Church, either by a solemn judgment or by her ordinary magisterium, as having to be believed.” Then a declaration on the necessity of faith, that “Since without faith it is impossible to please God and attain to the fellowship of His children, therefore, without faith no one has ever attained justification, nor will anyone obtain eternal life unless he shall have persevered in faith unto the end.” [27] The essential word in the second statement is evidently “faith.” But what kind of faith is meant. If it means an explicit Catholic faith, then Pius IX is wrong; if it means anything less, then his position on the prospective salvation of non-Catholics is implied in a solemn conciliar definition. Fortunately we do not have to resort to conjecture because the proceedings of the Vatican Council settle the question beyond dispute.

In the original draft of the dogmatic constitution, the pertinent passage, describing the necessity of faith, was logically connected with the preceding paragraph on the scope of Catholic belief. After giving the object of the Catholic faith, the docuмent continued: “This is that faith without which it is impossible to please God and attain to the fellowship of His children. Wherefore, just as without it justification never comes to anyone, so, no one, unless he shall have persevered in the same unto the end, will obtain eternal life.” [28]

But before the final and definite form was drawn up and presented to the council for acceptance, an important emendation was made and the reason for the change explained to the assembly by the delegate for the Commission De Fide. “We have made a substitution,” he said, “in the paragraph which begins, ‘This is that faith…’ The emendation of the beginning of this paragraph is the following, namely, that instead of the words, ‘This is that faith…’ there be substituted the following words, ‘Since, without faith, it is impossible to please God…Unless he shall have persevered in faith unto the end.’ I explained to you yesterday, Most Reverend Fathers, our reason for this change. The reason, to repeat in brief, is this: to remove the close connection between this and the preceding paragraph, lest it appear that an act of the Catholic faith is necessary for salvation, for all people. For this is false. I ask you, therefore, to accept the formula modified by us.” [29] They accepted the revised formula, verbatim, and the reason for the change, we may infer, was also accepted by the Vatican Council to be solemnly confirmed by Pius IX, that a person can reach heaven by professing that faith without which no one can please God, but not necessarily the explicit faith of the Roman Catholic Church.

If a person is united to Christ through "the bonds of charity," then the Council of Florence is, clearly, saying that "no other union is needed", which means that love, hence, obedience, to the commands of God are all that is needed for a person to be united to Christ, who is God, and hence, His Mystical Body, which is the Catholic Church.   Therefore, if a person, through no fault of his own, is simply ignorant of the commands of Christ (namely, to be baptized and submit himself/herself to the Roman Pontiff), then such a person could be in a state of grace through his/her implicit desire to receive the Sacraments, out of their love for God, who is Christ.  That is what the Council of Florence is teaching.

Quote

The subject of the salvation of sincere non-Catholics was on the agenda of the Vatican Council. [/b].

http://www.therealpresence.org/archives/Church_Dogma/Church_Dogma_032.htm