One of the things I have noted in the past is the phenomenon of Satanic ecumenism: the way in which people who hate each other are brought together in their mutual hostility to the things of God. We see it when the Pharisees and the Herodians conspire to kill Jesus. We see it when Pilate and Herod Antipas become friends as they humiliate Jesus in the passion. We saw it in the Hitler-Stalin pact. We see it when two thugs like Trump and Kim “fall in love”. And we see it in this story of Orthodox Jews falling for the white nationalism of the Alt Right.
One of the fascinating things about western religious communities, Jewish, Eastern Christian, Catholic, Islamic, and the various Protestantisms, is that all contain subcultures who are defined not so much by theology as pathology. They have wildly different theologies, but they have an extremely similar feel. They hunger for earthly power. They despise the weak. They define themselves in terms of enemies to be punished and destroyed. They see their relationship with God in terms of servile fear and salvation in terms of keeping rules and excluding the impure. They despise each other and yet are oddly peas in a pod–a sort of Screwtapian fellowship united by hate.
CS Lewis remarks on the opposite phenomenon as well. An Anglican writing to a Catholic convert, he says, “I believe that, in the present divided state of Christendom, those who are at the heart of each division are all closer to one another than those who are at the fringes. I would even carry this beyond the borders of Christianity: how much more one has in common with a real Jew or Muslim than with a wretched liberalising, occidentalised specimen of the same categories. Let us by all means pray for one another: it is perhaps the only form of “work for re-union” which never does anything but good.”
This echoes something in the Christian mystical tradition as well. “Beloved, let us love one another; for love is of God, and he who loves is born of God and knows God. He who does not love does not know God; for God is love.” (1 Jn 4:7–8). Likewise, Paul will say of the pagans on Judgment Day: “When Gentiles who have not the law do by nature what the law requires, they are a law to themselves, even though they do not have the law. They show that what the law requires is written on their hearts, while their conscience also bears witness and their conflicting thoughts accuse or perhaps excuse them on that day when, according to my gospel, God judges the secrets of men by Christ Jesus.” (Ro 2:14–16). And, of course, most famously, Jesus, in the parable of the sheep and the goats, shows us the judgment of “the nations” (that is those outside the visible covenant people who are as surprised as anybody to find themselves to be sheep welcomed into the kingdom) with these words: “Then the righteous will answer him, ‘Lord, when did we see you hungry and feed you, or thirsty and give you drink? And when did we see you a stranger and welcome you, or naked and clothe you? And when did we see you sick or in prison and visit you?’ And the King will answer them, ‘Truly, I say to you, as you did it to one of the least of these my brethren, you did it to me.’” (Mt 25:37–40).
In short, what unites the saved (whatever religion they professed on earth) is Love, because God is love. The Fundamentalist (of whatever religious persuasion, but especially the Christian fundamentalist) always attacks this with the assumption that this is a form of “salvation by works”. (He never, by the way, attacks “achieving exact theological precision” as a form of salvation by works.) The Fundamentalist talks as though loving your neighbor is the thing the sinner is doing in order to earn God’s love. But of course the biblical teaching is that love is the result of grace at work in the human heart, not the cause of it. The sheep who is saved did the right and loving thing because he was obeying the prompting of the Holy Spirit and, whether he realized it or not, acting as a disciple of Jesus Christ. Whatever flavor of religion you call yourself, if you love, you are cooperating with the grace of God and he is utterly without shame in his willingness to enter any human heart open to him. The atheist who sees the hungry and feeds him out of love is closer to the God who is love than the Ph.D with correct theology who does not love. That is the point of the parable of the Good Samaritan–who was likewise outside the visible covenant community.
Does that mean the Christian revelation means nothing and you can believe whatever you like? Of course not. We are bound to obey Jesus Christ once we realize that he is the only begotten Son, the Way, the Truth, and the Life, and that no one comes to the Father but by him. But though we are bound by the sacraments, God is not bound. So he can choose to be at work in the heart of anybody he pleases, including non-Christians. Our business is not to judge them, but to obey him. And obedience means love.