The exclusivist claims of Christianity are a subject of ongoing debate both within the Church and outside it. When President Ford was buried from the National Cathedral a while back and the traditional funeral gospel reading from John 14 omitted the concluding phrase, "No one comes to the Father but by me," that omission did not go unnoticed either by those who were inclined to applaud it or by those who were scandalized by it. The recent deposition of an Episcopal priest who also professed Islam, and the bishop-elect who also walks the way of Zen Buddhism, have kept the issue on center stage.
With Good Shepherd Sunday coming up, I ran across this from the late Anglican New Testament scholar Reginald Fuller in his homiletical notes on John 10:11-18 for the Fourth Sunday of Easter (from Preaching the Lectionary, 1984). It speaks to the question cogently:
(Referring to Article XXVII of the Church of England, Of Obtaining Salvation Only by the Name of Christ) In modern words, this article condemns the view that it is good to have a religion but it doesn't matter which one. The biblical exclusiveness that underlies the mission of the Church can be linked with ... the parable of the sheep and the shepherd: "I have other sheep that are not of this fold; I must bring them also, and they will heed my voice. So there shall be one flock, one shepherd." Perhaps, too, the "wolves" against which the good shepherd defends his flock are those broad-minded Christians today who hold that salvation is through any religion, not through Christ alone. This is exclusive claim is made because only Christ has been raised from the dead. Only he has passed through death to our final destiny, and therefore we can attain our final salvation only through him.