The religious factor, used to support the “traditional closeness”,2 would place Greece in the trend of “occasional community”, were it not for the rivalry between the two patriarchates, which gives Russian-Greek contacts a particular dimension. The ROC’s primacy in the universal Orthodox Church has a crucial significance for the credibility of Russia as an Orthodox civilization. Acting as patron of the dialogue between Christianity and Islam requires that the ROC be treated in the international arena as the unquestioned leader of world Orthodoxy, with a mandate to speak in the name of all the churches. Only Constantinople can challenge Moscow in this sphere.