LUMEN GENTIUM SEEN AS HISTORICAL: PRECEDENTS IN THOMAS AQUINAS AND CHURCH FATHERS IGNORED

St. Thomas Aquinas taught that a person in ignorance could be saved even if he was not a member of the Catholic Church. St. Thomas saw this as an exception to the visible need of the baptism of water for salvation . St. Thomas Aquinas also taught that everybody without exception needs to enter the Catholic Church for salvation. Extra ecclesiam nulla salus.

So the exceptions in Lumen Gentium (to the need of the baptism of water for salvation) have been preceded in the writings of St. Thomas Aquinas (De Veritate 14, A- 11 ad1.) http://www.youtube.com/watch?v=sNiO7NWawCs . Also, in the writings of other saints and the Church Fathers. Lumen Gentium has only repeated those teachings. It is not there for the first time in Lumen Gentium or elsewhere in Vatican Council II.

Lumen Gentium 16, Vatican Council II: For they who without their
own fault do not know of the Gospel of Christ and His Church, but yet seek God with sincere heart, and try, under the influence of grace, to carry out His will in practice, known to them through the dictate of conscience, can attain eternal salvation."

St. Gregory of Nazianzus, Oration 18.5 [at funeral of his father, a convert] :( c. 374 AD): "He was ours even before he was of our fold.
His way of living made him such. For just as many of ours are not with us, whose life makes them other from our body [the Church], so many of those outside belong to us, who by their way of life anticipate the faith and need [only] the name, having the reality."

St. Justin Martyr, Apology 1.46 (c. 150 AD): "Christ is the Logos [Divine Word] of whom the whole race of men partake. Those who lived according to Logos are Christians, even if they were considered atheists, such as, among the Greeks, Socrates and Heraclitus."(Emphasis added)

Over centuries the Church taught that de facto everybody needs to enter the Catholic Church to go to Heaven, extra ecclesiam nulla salus.

However in principle (de jure) there can be exceptions to the ordinary means of salvation  i.e Catholic Faith and the Baptism of water. For example even atheists can be saved in principle and as an exception. Atheists cannot be saved de facto and in general since Catholic Faith and the Baptism of water is the de facto and general means of salvation according to the dogma of Unam Sanctam and the Council of Florence.
There are exceptions in principle  known only to God. We cannot judge that someone has a genuine baptism of desire. The Letter of the Holy Office 1949 specifically covers this point mentioning   ‘certain circumstances’ .

Mark Shea  presents Lumen Gentium as ‘another fact in Catholic history' which can  balance the Church teaching’ of extra ecclesiam nulla salus.

‘… neither can we dodge another fact of Catholic history: the Second Vatican Council. At that council, 660 years after Unam Sanctam, the Church formulated Lumen Gentium, in which she declared, "The Church knows that she is joined in many ways to the baptized who are honored by the name of Christian, but do not profess the Catholic faith in its entirety or have not preserved unity or communion under the successor of Peter."
So is there a more balanced picture that reverences both Unam Sanctam and Lumen Gentium as authentic magisterial teaching? Yes…’

Note: He presents Lumen Gentium as 'another fact in Catholic history' even though  Lumen Gentium is a repetition of St. Thomas Aquinas and the Church Fathers. It is not a new teaching.

Those who are saved implicitly ; 'who are in some kind of union with the Church' and are not baptized with water are included by Mark Shea with those who are saved explicitly in the general, ordinary means of salvation. This mix up is contrary to the dogma which was clear and precise.

The dogma only referred to de facto, explicit salvation as the ordinary means of salvation.This was the model of St.Thomas Aquinas and the saints.

We declare, say, define and pronounce, that it is absolutely necessary for the salvation of every human creature to be subject to the Roman Pontiff. – Unam Sanctam, Pope Boniface VIII,1302

The Holy Father is referring to the de facto ordinary means of going to Heaven and avoiding Hell for all people in general.

De jure there could be exceptions, in certain circumstances, known only to God. We cannot judge.Mark Shea mixes up the de facto and de jure means of salvation  in his article Can Non Catholics be Saved? in InsideCatholic.com .