“I am convinced that the question of the final union of all Christians remains, indeed, unanswerable. One must not forget that this question also includes the question of the union between Israel and the church. At any rate, to me the notion that one could achieve unity through a “really general (ecumenical) council” is a hybrid idea. That would be tantamount to building another tower of Babel which would necessarily result in even greater confusion. Complete union of all Christians will hardly be possible in our time. However, that unity of the church which already exists indestructibly is a guarantee for us that this greater unity will happen in the future. The more one strives for this unity with all one’s might the more Christian one will be.”
Joseph Cardinal Ratzinger, “Luther and the Unity of the Churches: An Interview with Jospeh Cardinal Ratzinger“, Communio 11, no. 3 (1984): 226.