The late Archbishop Seraphim (Sobolev) wrote: "It is difficult to say where Orthodox ecumenists deviate from the Orthodox faith more: in their writings, or by participating at Ecumenical conferences" . This participation involving the acceptance of dogmatic compromise and departure from Holy Tradition is, in its essence, betrayal of Orthodoxy. Many things have changed in the consciousness of local Orthodox Churches, including the Moscow Patriarchate, since they joined the Ecumenical movement .
At their Moscow Council of 1948 the Moscow Patriarchate defined the "ecumenical movement as a new attempt to erect the tower of Babel, as a sign of a usual delusion of man... based on his vice of pride. It has replaced the task of an inner, organic and dogmatically based unification by an external mechanical unification." It is extremely significant that at that time the MP thought that "true Church unity was a foreign concept to the understanding" of ecumenical movement, and that to embrace it would mean "to reject true Church unity... in space and time... to break the uninterrupted chain of grace uniting the Orthodox Church with the holy Apostles through the Apostolic succession... to sell off our zealously guarded treasure of faith for the mess of pottage of earthly benefits and to thereby participate in ensnaring of human souls" .
These last words sound particularly bitter, when they are compared with present-day praises sung in honor of ecumenism by "Orthodox" ecumenists of the Moscow Patriarchate.
Apart from the deviation of these "Orthodox" ecumenists from their faith through violating of holy canons and the dogma of the Church, (which we confess in the 9th article of our Creed), ecumenism has produced other bad fruits. Particularly, friendship which develops among ecumenists. Imperceptibly for themselves participants of ecumenical gatherings deviate from their former convictions and acquire a special language, terminology and a way of thinking which develop in the process of dialogue. Thus is attained the estrangement of Orthodox ecumenists from their Mother-Church, the darkening of their consciousness by the non-Orthodox heretical delusions. Just as the holy Apostle Paul observed:
"evil communications corrupt good manners" (1 Cor. 15, 33).
There is such a concept as "spiritual chastity" (Archimandrite Konstantin Zaitsev) without which faithfulness to Christ is unthinkable. According to a contemporary religious writer "ecumenical gatherings, prayers and concelebrations foster constant infidelity of the participants to their own faith, and inculcate a malicious state of spiritual adultery into their souls" .
Ecumenists have long since been aware of the importance of personal communication for the cultivation of confessional indifference and unscrupulousness. They have a good reason not to limit themselves solely to printed publications; above all they particularly encourage personal contacts which are established at their conferences, assemblies, all kinds of dialogues and gatherings.
In the West, as a rule, ecumenism has been propagated on a mass scale for decades, aiming, first of all, at the demoralization of the Orthodox faith: other confessions being of no particular interest to the enemy of mankind, because they are already partly, or fully in his power.
Functionaries of Ecumenical Movement, both in the West and especially in Soviet Russia, have always been greatly attracted by free trips abroad and to all the related benefits.
Theological schools of the Moscow Patriarchate are being demoralized with the aid of ecumenism according to a plan which is intended to project many decades into the future. Intending priests are openly inoculated with the ecumenical world view instead of the Orthodox faith. Many of them are being sent to study at the ecumenical centers in the West, while many foreign non-Orthodox students are studying at the theological seminaries and academies of the MP, and getting their theological degrees (!) there. Western heretics are invited not only to give an occasional lecture, but entire courses. Thus, in a course of a number of years, at the end of the 70-ies and the beginning of the 80-ies, Professor of the Eastern Institute in Rome, Jesuit Michael Arranz, lectured in Liturgies at the Leningrad Theological Academy. He himself had received a PhD in Theology from the hands of "Orthodox" Metropolitan Nikodim (Rotov), and robed as an Orthodox priest, had partaken of the Holy Communion in the sanctuary of the Academy's church.
Thus, confirmed betrayers of Orthodoxy are formed in the MP. During the years of "reconstruction", hundreds of parish priests of the Moscow Patriarchate were only too happy to participate in the "exchange scheme" and to be worked upon in Protestant and Catholic communities in the West, while countless western missionaries, due to the benevolent connivance of the MP have been openly engaged in corrupting Orthodox people in Russia. As the patriarchal archpriest Ioann Sviridov recently said while in Rome: "Russia is the land of mission" . And most recently, there has begun a direct bribing of Orthodox clergy of the MP by Catholics. Indeed, all these excesses and crimes of ecumenists are nothing but a "spiritual adultery"!
This expression has been used by priest Timofei Selsky .
Banquet following one of the ecumenical conferences
 Archbishop Seraphim (Sobolev), the report "Nado li Russkoi Pravoslavnoi Tserkvi uchastvovat' v ekumenicheskom dvizhenii?" (Should the Russian Orthodox Church take part in the Ecumenical Movement?" in the collection "Deianiia Soveshchaniia glav i predstavitelei Avtokefalnykh Pravoslavnikh Tserkvei..." (The acts of the Conference of the Heads and the Representatives of the Autocephalous Orthodox Churches...) , vol. 2, Moscow, 1949, p. 376.
 The Moscow Patriarchate (MP) Became a member of the World Council of Churches in 1961 at the 3rd Assembly of the WCC in New Delhi.
 "Deianiia Soveshchaniia glav i predstavitelei Avtokefalnykh Pravoslavnykh Tserkvei..." (The Acts of the Conference of the Heads and the Representatives of the Autocephalous Orthodox Churches...), vol. 2, pp. 414-415.
 Tuskarev A., op. cit., p. 60
 See Footnote .
 Priest Timofei Selsky, "O dukhovnom tselomudrii" (On spiritual Chastity), Orthodox Russia, Jordanville, 1995, No. 1 /1526, p. 9.