Here's the state of the question on explicit and implicit faith in Christ, per 3 pre-Vatican II authorities, for our reflection. Note the careful wording in Msgr. Fenton, Fr. Mueller, St. Alphonsus etc, in order to allow for the view of justification through implicit faith, but final salvation coming only after explicit faith in Christ, which Cardinal De Lugo, whom St. Alphonsus highly respects, also defends at length. That the OT just in limbo were saved in this way is also a defensible view; through implicit faith before Christ, and arriving at explicit faith in Him after His Coming there, and thereafter immediately going to Heaven to experience the blessed vision of God face to face forevermore. Thus, it is defensible to say, persons can be justified by an act of contrition, and obtain perseverance after explicit faith.

Fr. Sylvester Hunter, in Outlines of Dogmatic Theology (1895) writes: "112. The Catholic Doctrine.—In opposition to all 112] THE CATHOLIC DOCTRINE. 159 these, the doctrine of Catholic theology is that the body of public revealed doctrine has received no objective increase since the days of the Apostles. It is true, as St. Thomas remarks, (Summa Theol. 2. 2. q. I. a. 7. c.) that the whole of the Divine economy of salvation is in some sense contained in the two fundamental articles which have been revealed from the beginning, that God is, and is a rewarder of them that seek Him : the explicit belief in which truths is and always has been a necessary condition of salvation, according to the doctrine of St. Paul. (Hebrews xi. 6.) But the whole body of Christian doctrine could never have been discovered as contained in this primitive and, so to speak, elementary revelation, had not further revelations been vouchsafed ; and such revelations were given from time to time under the patriarchal dispensation, under the Mosaic Law, and during the life of Christ and His Apostles ; ...

"Regarding the points on which explicit knowledge is required as the indispensable means of justification, this certainly extends to the belief that God exists and that He shows Himself the Rewarder of them that seek Him.  This amount of belief is declared by St. Paul to be essential, if any one will please God. (Hebrews 11:6). The Greek word Rewarder literally means the payer of wages: the seeking God is therefore the application to enter His service; and the absolute necessity of the knowledge specified will be readily understood, if anyone is to earn a reward.

So far there is universal agreement, and in fact the necessity that we have stated is not open to doubt, for Pope Innocent XI condemned the assertion that explicit belief that God rewards is not necessary (prop. 22; Denz. 1039).  There is a controversy whether St. Paul, in the passage quoted, intended to mention all that is necessary, or whether explicit belief in the Trinity and Incarnation is required. At one time, a few writers were found to maintain that this explicit belief not only is necessary, but always has been so: this is now held by no one but many followers of the Thomist school hold that it has been necessary since the revelation was brought by Christ, although under the Old Law it was not requisite. These found their opinion upon the language of Scripture, which frequently speaks of faith in Christ as the essential condition of salvation; and to believe in Christ means to believe that He is God and Man."

Fr. Michael Mueller, CSSR, citing St. Alphonsus and other authorities: "Some theologians hold that the belief of the two other articles - the Incarnation of the Son of God, and the Trinity of Persons - is strictly commanded but not necessary, as a means without which salvation is impossible; so that a person inculpably ignorant of them may be saved. But according to the more common and truer opinion, the explicit belief of these articles is necessary as a means without which no adult can be saved.”

Msgr. Joseph Clifford Fenton, writing during the reign of Pope Ven. Pius XII: "most theologians teach that the minimum explicit content of supernatural and salvific faith includes, not only the truths of God’s existence and of His action as the Rewarder of good and the Punisher of evil, but also the mysteries of the Blessed Trinity and the Incarnation"

Edit: Ladislaus, note to you: I saw your post only after typing this. I will respond to you subsequently. God Bless.

At one time, a few writers were found to maintain that this explicit belief not only is necessary, but always has been so: this is now held by no one 

Not so fast.  I want to make sure that you accept the infallible decree from the Council of Trent, as it is written.  Isn't that what the Feeneyite heretics always say they do?  They believe the dogmas as they are written? Here again is what the Council infallibly teaching is necessary for salvation:  

CANON VI.--If any one denies that sacramental confession was instituted by divine law, or is necessary to salvation; or saith, that the manner of confessing secretly to a priest alone, which the Church hath ever observed from the beginning, and doth observe, is alien from the institution and command of Christ, and is a human invention; let him be anathema.

Three questions:

1) Do you agree that sacrament of confession is necessary to salvation, as the infallible decree teaches?  If not, you are anathema.

2) Do you believe a person can be saved without sacramental confession (e.g., The Blessed Mother, baptized children who died before reaching the age of reason, etc.)?  

3) If you answered yes to number two, I want to know "if you can see the contradiction that it is to the dogma as decreed at Trent"?

Indeed, you have to have sincere contrition for and the intention to confess every mortal sin; in other words, you can't be deliberately hiding or holding back on any.

Certainly, if there is such a thing as BoD, then I believe that an explicit intention would be necessary.  If you look at what Trent taught about Confession, initially the text read that perfect contrition sufficed to restore a soul to justification.  But the Pope, inspired by the Holy Spirit, intervened and insisted that the condition also of intending to confess the sin be added as necessary.  And that is what Trent taught infallibly.  Certainly the intention to confess could be read implicitly into perfect contrition.  I mean, if you're perfectly contrite, then you implicitly also would intend to make whatever act of reparation God requires, including Confession.  So this notion that the intention to confess would be implicit in perfect contrition was rejected by Trent for Confession.  So why should we imagine that an implicit intention could suffice for Baptism ... when Trent taught that it does NOT suffice for confession?  There's no reason to believe this, and it's a huge stretch.  So you raise a very important point that I had not completely thought through before.

PS ... too many Traditional Catholics falsely believe that one need only have perfect contrition to be restored to a state of justification.  But Trent teaches that this does not suffice but must be combined with the intention to confess those sins as soon as it is reasonably possible.

I've used this analogy before, for Baptism, but it also applies to Confession.  We have a man who loves a woman deeply, proposes (and she accepts), sets a date, rents out a hall, sends out invitations, and schedules everything with the priest.  But now, 5 minutes before the actual vows, he gets cold feet and bails out.  Despite ALL his intentions, he was never married.  So, with Confession also ... and Baptism.  I can be deeply sorry, but unless I intend (vow, even) to go to Confession, then I'm not really sorry and am not restored to a state of grace (per Trent).  And, so also with Baptism.  Even if one believes that Trent taught BoD, the word Trent uses is votum, which in Medieval Latin meant a solemn vow (like the ones pronounced at marriage or by a religious) ... and our word "vow" derives from this word as well.  There is no indication anywhere among the Church doctors or in the Magisterium that BoD can ever apply to anyone other than a catechumen.

Thank you for helping me reach my conviction. For me this doctrine is at the very core of why I believe the reform to be an error because I believe in veritas ante caritas. If we concede that the doctrine of BoD is correct, then we must also agree that charity comes before Truth. V2 would then be correct and simply outline the truth. We would then be in error, if we reject V2. If the BoD doctrine is correct, then God's Church must includes all religions and even atheism and there would be no point to be Catholic or otherwise.

In today's Gospel, the owner of the vine, tells the labourers that he is free to pay whatever he wills to whomever. But in the same passage it is clearly underlined the importance for man to work for his pay.

These are two Truths are only apparently in contradiction (*) and they reinforce two concepts:
1. God can save anyone.
2. Man must do the right thing regardless.

(*) It is only an apparent contradiction that while God can save anyone, He still requires all to work for salvation.

I interpret (2) to mean that man must "work" for his baptism; i.e. he must have the explicit intention to be baptized. This, for me, excludes the "implicit" BoD interpretation.

You just committing the alleged crime of interpreting the dogmatic decree (as if everything that is written doesn't require interpretation).  It clearly states that "anyone who denies that sacramental confession ... is necessary to salvation ... is anathema." You say you believe it in one breath, and the contradict yourself in the next by saying a person can be saved without sacramental confession.