No, I never supposed you were a perennialist, your curiosity and somewhat sympathetic ruminations notwithstanding, or not at least in the sense that the Schuonian uses the term. I agree, and have acknowledged the fact in my writings, that most Christians historically have been either exclusivists, who believe everyone else is damned, or inclusivists, who insist that only Christianity is fully true, though other religions may contain partial truths. It’s clear your “Christian humanism” is a variation of the latter position.

I agree that one can’t be a Christian without believing that all salvation comes through Jesus Christ. The question, however, is whether this Christ, the eternal Logos, bound Himself irrevocably through the events of the Gospel to a particular form and whether Christianity must therefore be identified with the “scandal of particularity” you associate with Barth and Brunner. While there are Patristic exceptions, of course, the consensus of the Fathers and Councils would seem to be otherwise. “Though Christ was in the body,” says Saint Athanasius, “He was not circumscribed by that body.”