Recently a friend asked on whether “Christianity is always about exclusiveness.” To put it in other words, somehow we really like to determine who is in and who is not. Coincidentally, I just read a book on partition of Judaeo-Christianity, on how “the Judaism” (admittedly an anachronistic term, hence I am using it retrospectively) of the first century AD was split into rabbinic Judaism and Christianity. And the author argued that the notion of “religion” itself, the question of “who is in and who is not”, is perhaps invented by the early Christians. Previously (and, yes, even into our days), “religion” and “race” are intertwined. You don’t choose whom and what you believe; you are simply born into it. Once a Jew, always a Jew. Hindu/India. Chinese tradition. And so on.
On the other hand, it posed a new question to the early Christians: What constitutes a Christian, if there is neither Jew nor Greek? And hence perhaps then we came up with the notion of “heresy” and “orthodoxy.” And hence we came up with the notion of “religion” itself. Paradoxically, our universality (that it embraces all races) implicates in our exclusivity.