Updated: Though it had actually started slowly in its modern phase during the pontificate of Pius XII (click), it was doubtless the seemingly radical abruptness of the Church's turnaround regarding ecumenism especially since the Second Vatican Council which has caused some ultra-traditionalists to suspect it, or even to condemn it, as though it were something wrong in itself. Rather than appreciate how long and how carefully the Church studied the phenomenon, they panic. Yet however much we may regret some of its parochial manifestations in the postconciliar period, ecumenism cannot be condemned per se, for the Church has always engaged in it in some degree; and it is the prerogative of the Holy Father, who holds the Keys of the Church, signifying the "care of the whole Church and its government," the "gift of ecclesiastical authority in its widest scope," (CE , 1913, vol. VIII, 632) to discern the particular dispositions on the part of those outside her bounds in any given era. Its forms change according to the times, certainly, but the Church's solicitude is ever one of hope, dialog, and active seeking as history shows.
To illustrate the truth of this one need look no further than the Council of Florence, the 17th Ecumenical Council of the Church which sought (an important word here) to reunite the Orthodox Churches to the Catholic faith. This council had as its objective "the reunion of the Churches, reforms, and the restoration of peace between Christian peoples" (CE, 1913, vol. VI, 112) This sounds very similar to the stated objectives of the Second Vatican Council's ecumenical movement in the 20th century.
"The Greeks soon appeared at Ferrara (where they met first in April 1498), headed by the Emperor John Palaeologus and Joasaph, the Patriarch of Constantinople, and numbered about 700" (ibid).
And during its sessions there was much successful effort to find practical solutions to the dogmatic problems which had separated the Latins from the Greeks, e.g., the Filioque, Purgatory, the Azymes, and the primacy of the Bishop of Rome (no small considerations!). The council was soon transferred to Florence where compromise formulas regarding the Procession of the Holy Ghost were sought and agreed upon (after much dialog and despite -- as one must expect -- some hotheads on both sides ready to cry foul). Agreements were also reached on other important controverted matters. This is the ecumenical way of the Church!
Meanwhile the Catholic Church sought (that word again!) to reconcile also other Eastern Churches (the Jacobites of Syria, 1442, the Mesopotamians, 1444, the Nestorians and the Maronites, 1444). All of these churches, though separated from Rome, had elements of the Catholic faith and valid sacraments by virtue of their historical relationship and unity with the faith. Was the Church to play the part of the Pharisee with these?
Alas, when the Orthodox representatives of the Council of Florence went back to their home countries and reported the healing of the great schism, it was not accepted by the people. Historic prejudices ran deep and the common Orthodox man was not acquainted with or concerned about important theological terms and subtleties. This grieved the Pope and the Church most profoundly. It frustrated its dialog and "ecumenism" -- for a time. But it also revealed the loving solicitude of the Church in a way that illumines our own time.
Needless to say it is often the vicissitudes of the times as well as the dispositions of those outside the Church, as we mentioned above, which determine whether the Pope and Church deem it wise or ill to actively promote such ecumenical actions and strivings toward legitimate and faithful compromise formulas at any given time. Traditional Catholics have sometimes in their love for Tradition forgotten this. Sometimes the Church's approach will differ depending on who it is the Church is trying to reconcile through dialog and official exchanges.
"Heresy . . . differs from schism." Schismatics, says St. Thomas, in the strict sense, are they who of their own will and intention separate themselves from the unity of the Church.
Unity, the Angelic Doctor says, "consists in the connection of its members with each other and of all the members with the head. Now this head is Christ whose representative in the Church is the Supreme Pontiff. And therefore the name of schismatics is given to those who will not submit to the Supreme Pontiff nor communicate with the members of the Church subject to him. Since the definition of papal infallibility, schism usually implies the heresy of denying this dogma. Heresy is opposed to faith; schism to charity; so that, although all heretics are schismatics because loss of faith involves separation from the Church, not all schismatics are necessarily heretics, since a man may, from anger, pride, ambition, or the like, sever himself from the communion of the Church and yet believe all the Church proposes for our belief (II-II, Q. xxix, a. 1). Such a one, however, would be more properly called rebellious than heretical." (CE, 1913, vol. VII, 256)
Remarking on deficient notions regarding the Church and her own pleroma of unity, Cardinal Ratzinger, in a book condemning liberation theologian Leonardo Boff, puts it this way:
". . . In order to justify [his position], L. Boff appeals to the constitution Lumen Gentium n. 8 of the Second Vatican Council. From the council's famous statement, 'Haec ecclesia (sc. unica Christi ecclesia) Catholica subsistit in ecclesia Catholica' (This Church -- namely the sole Church of Christ -- subsists in the Catholic Church), he derives a thesis which is exactly contrary to the authentic meaning of the council text, for he affirms: 'In fact it (sc. the sole Church of Christ) may also be present in other Christian churches' (p. 75). But the council had chosen the word subsistit -- subsists -- exactly in order to make it clear that the one sole 'subsistence' of the true Church exists, whereas outside her visible structure only 'elementae ecclesia' -- elements of the Church exist: these being elements of the same Church tend and conduct toward the Catholic Church (Lumen Gentium, n. 8). The Decree on Ecumenism expressed the same doctrine (Unitatis Redintegratio nn. 3, 4) and it was restated in Mysterium Ecclesiae ." (Cardinal Ratzinger, On the Unity of the Church: (U.S. Catholic Conference Documentary Service, April 4, 1985, vol. 14, n. 42, pp. 685-686))
Sometimes it will evidently depend on whether a person or group is the perpetrator of the theological crimes of heresy or schism or whether they simply inherited the problem through no fault of their own. As Michael Davies, echoing the council, says in his book I Am With You Always:
"A man born and brought up in a heretical sect may live and die without ever having a doubt as to the truth of his heretical beliefs. Where heresy is adhered to from involuntary causes, such as inculpable ignorance of the true creed, erroneous judgment, imperfect apprehension, and comprehension of dogmas, it is not an act of the will, and the heresy is only material and does not incur the guilt of sin." (Neumann Press, p. 46)
Thus any number of factors may influence a person's relationship to God and how the Church regards a group or persons separated from the Church in some degree in a given era.
Florence and the Mass
At the Council of Florence, prior to the people's rejection, "An amicable agreement was also reached regarding the form of consecration in the Mass" (ibid). The dialog here was fruitful. Serious differences over the Mass are not new to our day. The point is that the Church was and is willing to do all it can when it perceives -- or at least has reason to hope for -- the goodwill of the representatives of those separated from her. This is not to say the Pope could not in justice demand that the schismatics simply "return"-- unconditionally -- and accept all the ready-made theological formulas that the schismatics find it so hard to accept. But the Church practices more (not less) than mere justice. Like Christ, she ever seeks the "spirit" and not only the "letter" of the law, which, St. Paul says, only "kills" (condemns). The Church is ever ready, like her Lord Jesus the Good Shepherd -- and unlike Pharisees of every age -- to leave the ninety-nine who are safe in the fold to go after the single lamb which has somehow strayed and seek to bring it back. This "seeking to bring the lost back" reflects an active "seeking" which is what the Church's ecumenism is all about. Only Pharisees, or misguided souls, find such love offensive per se. After all, have we not also all gone astray like sheep and need the grace of God? And, St. Paul asks, what do we possess which we have not been given? Surely we are not Christians by our own lights and goodness! The Church, as the Light of the world, seeks to share the grace of God with all and who are we to begrudge it?
In the 20th century, with the Second Vatican Council, the Church evidently once again judged it time, after long observation, to actively seek out those who had strayed, having carefully observed the evolving dispositions of the heirs of the separated churches -- and the secular world -- during the first half of that century. Will it succeed this time? The dangers (as always) are present and real -- perhaps more than in any previous time due to the universal tendency of indifferentism which the Popes of the first half of the century warned about. But none can question the Church's patience or blame the Church, when she so judges, for risking such love and solicitude. Her love has always evidenced the willingness to leave the ninety-nine and to seek after those sheep who have strayed.
Catholic ecumenism -- not its distortions! -- is of the essence of the Church to the extent that the Church will always care for those with whom she has been related historically and sacramentally. A Mother never ceases to long for the return of her children who have left and gone astray. Pre-Vatican II Catholics and the Greek Orthodox -- surrounded by many common enemies -- prayed together for unity at the Council of Florence. How could they not? It is the sick, not the well, who need a physician. Only the Pope and the Magisterium can judge what kind of solicitude toward those separated from the Church (not the heresy!) is required in any given era (in some eras, strict, even harsh; in others not so). This, again, is not to say that the Church does not risk rejection, contempt, or even behave naively herself at times. Florence showed how the Church loved and "lost" in a given era.
The Church at the Council of Trent also guaranteed and granted safe conduct toward Protestants who wished to attend and dialog and promised them an attentive and fair hearing at the council (Safe-Conduct Granted to Protestants, session 13, Trent.U? ) The Church longed to dialog with them.
"The sacred and holy, general Synod of Trent, lawfully assembled in the Holy Ghost, the same Legate and Nuncios of the holy Apostolic See presiding therein, grants, as far as regards the holy Synod itself, to all and each one throughout the whole of Germany, whether ecclesiastics or Seculars, of whatsoever degree, estate, condition, quality they be, who may wish to repair to this oecumenical and general council, the public faith and full security, which they call a safe conduct, with all and each of the necessary and suitable clauses and decrees, even though they ought to be expressed specifically and not in general terms, and which it is Its wish shall be considered as expressed, so as that they may and shall have it in their power in all liberty to confer, make proposals, and treat on those things which are to be treated of in the said Synod; to come freely and safely to the said oecumenical council, and there remain and abide, and propose therein, as well in writing as by word of mouth, as many articles as to them shall seem good, and to confer and dispute, without any abuse or contumely, with the fathers, or with those who may have been selected by the said holy Synod; as also to withdraw whensoever they shall think fit. It hath furthermore seemed good to the holy Synod, that if, for their greater liberty and security, they desire that certain judges be deputed on their behalf, in regard of crimes whether committed, or that may be committed, by them, they shall themselves nominate those who are favorable towards them, even though the said crimes should be ever so enormous and should savor of heresy" (13th Session Council of Trent chapter VIII).
Again, this shows the Church's love and solicitude toward those who have strayed from her.
Ecumenism (which is a part of the Church's evangelism and love, albeit oriented to those who were once within her bosom) takes the form of an active going out toward the separated or lost. In this way the Church follows the Good Shepherd and Physician. Arrogance and unforgiveness or historical vengeance find no place in her, the Bride of Jesus Christ who gave His life for sinners.
Just as the God of Israel called His wayward people back time and time again, so the Church, being the Mystical Body of Christ and People of God, seeks to call back those who have gone their own way. There are always dangers which accompany this love. Some may indeed mistake it for indifference. But Christ did not despise the cross in calling sinful mankind back to His bosom through His dialog of beatitude and invitation. Neither does the Church, His Body. Nor did our Lord, or His Blessed Mother, leave the charged atmosphere and theological factionalism of the Temple during the long years that Jesus was growing in stature and wisdom before the God and man and retreat, like the Essenes, into the desert as some "true" Temple and "true" Israel of God. No. Jesus ever called the Temple His "Father's House . . . a House of Prayer" and remained there, despite all the disputing between the Pharisees, Sadducees, and the others. Jesus did not separate Himself from sinners. Nor did He forsake the good Samaritan, who, although he held to unorthodox views, showed, our Lord said, more of the love of God in assisting the poor and wounded than all the Levites who, on their way to prayer, knew only their legalistic theology.
Nor did He forsake that pagan Roman, the Centurion, who displayed a faith hardly seen in all of Israel. Nor even the Good Thief who, dying on the cross next to our Lord, had more reason to despair than hope, and yet hoped as He looked on the tender Savior who so loved sinners and drew them by grace toward redemption. And if He did look harshly on the Traditionalists of His day, the Pharisees, who preferred the letter of the law to its spirit, even among them He sought out those who were willing to listen and respond, like Nicodemus.
Note: The above is my best understanding of the Church's approach to ecumenism which began in earnest in modern times with Pope Pius XII when he called for "well qualified" theological experts to engage non-Catholic followers of Christ (click) with a view to helping them see the Christ-given oneness and unity of the Petrine Church, the principle of ecclesial unity. Nothing above should be construed as advocating indifferentism relative to these issues. More than I once did, I think the best efforts of those who call themselves traditional Catholics in communion with the whole Church and magisterium (Dietrich and Alice von Hildebrand, Michael Davies, et al) have done a service by doing their part to keep the parameters of ecumenism in full and uncompromising focus.
It is noteworthy that pre-conciliar popes did not shrink from solicitously calling Protestants "Christians":
Pope Pius IX:
It is therefore by force of the right of Our supreme Apostolic ministry, entrusted to us by the same Christ the Lord, which, having to carry out with [supreme] participation all the duties of the good Shepherd and to follow and embrace with paternal love all the men of the world, we send this Letter of Ours to all the Christians from whom We are separated, with which we exhort them warmly and beseech them with insistence to hasten to return to the one fold of Christ; we desire in fact from the depths of the heart their salvation in Christ Jesus, and we fear having to render an account one day to Him, Our Judge, if, through some possibility, we have not pointed out and prepared the way for them to attain eternal salvation.
And Pope Benedict XV (15):
In every age it has been the concern of the Roman Pontiffs, Our predecessors, and likewise it concerns Us greatly, that Christians who have, unfortunately, withdrawn from the Catholic Religion should at length be recalled to us as a forsaken Mother.
Subsists: St. Thomas Aquinas held...that the human soul subsists (has its existence of itself, not through the existence of the body) and could not have emerged from matter and material forces but must be directly created by God. --- This post updated 1x