“The gentile makes gods of stone and we of theories.”
Isaac Bashevis Singer
(1) Is G-d true?
(2) Is G-d central to human perfection?
Judaism is not any particular combination of answers to these two questions.
If you answer no to both, you are what’s called an atheist. Atheism is the idea that G-d is not there, and that He plays no role in human perfection, which must be defined in terms of the human beings themselves. Atheism, however, is viewed as so contrary to logic that it is rarely mentioned in Judaism. It is, after all, merely an intellectually bankrupt form of idol worship and a spiritually bankrupt form of humanism.
Idol worship (a very common and relatively rational position) says G-d is true but that He is not central to human perfection. That is, there is such a thing as a Most High being, but that Most High being has abandoned the earth (or at least shared it) with lesser powers. G-d made the thunder, but some other being or concept rules it now; whether that concept is electromagnetism or Thor really makes no practical difference. G-d gave us a mind so we could bend these beings and concepts to our will, through sacrifice and understanding, to extend and improve our being. For the idolator, G-d answers a couple of bothersome questions so the real business of life, the navigation of the various finite powers, may begin. Judaism has been anti-idol since Abraham reached (or began to reach) intellectual maturity.
The opposite of idolatry is a dying art called “enlightened humanism” that says it does not matter if G-d is not technically true, since He is the center of a well-ordered life. In the beauty of art or the profound joy and pain of the human experience lies something once rightly called other, sublime, otherworldly. If philosophy cannot prove that these experiences point to an actually existing Infinite Creator, that makes little difference, since so much of our greatest artistic and intellectual endeavors point toward that Creator. Humanism is like the Pantheon in Rome. A beautiful classical structure with a high dome, at the center of which there is a hole, which at the time of its construction demonstrated a wondrous innovation in engineering: The building is no less beautiful, and can continue standing, even if the piece at the top and the center is missing. Judaism, of course, is founded on that center stone having taken us out of Egypt with miracles and wonders.
If you answer yes to both of the above questions, you are what is considered “traditionally religious.” You say that G-d’s Truth and His centrality to the human endeavor are one; G-d is both real, and I exist for Him. I am not sure you have yet discovered Judaism, however. The Rambam (never mind his kabbalistic critics like the Maharal) would tell you that calling G-d “true” is a gross intellectual error, and that all scriptural or rabbinic sources calling Him just that must be understood in the utmost negative abstraction, their names made possible only by revealed prophecy. A human mind landing on some notion called “truth” and then ascribing it to G-d? Preposterous. The Yiddish word for G-d is der Aibishter. The One Who Is Above, eternally above, above the thing we are conceiving Him of right now.
By the same token, to call G-d central to human perfection is so gross a contextualization as to be factually false. G-d in His Infinitude is far beyond being any basis of perfection humans may strive for, even moral perfection. Is this not the very essence of the chok, the suprarational decree no human being could possibly devise had the Torah not decreed it? We do not keep kosher for health or to have a nice ritual to make our community cohere; none of these can possibly explain the precise workings of the halacha, and bizarre cynical contrivances involving Rabbis making things up based on the norms of repudiated surrounding pagans (or the like) must come into play. This cynicism is important if you are traditionally religious; the Jew doesn’t need it, because he doesn’t have to answer yet to both questions.
Now, the Jew doesn’t deny that G-d being true and being central to human perfection are trivially (if not technically) correct. In this sense, traditional religion can serve as a vessel for Judaism, a sort of ideological shorthand for what it does not capture. Judaism as it speaks to these questions, if it is forced to speak to these questions, is like traditional religion. The problems start when that vessel coarsens and darkens, losing its role as a mere interface through which Judaism speaks to certain narrow definitions and becomes the definition itself. And when that happens, the other answers to the questions become incredibly useful.
If someone is getting too comfortable both intellectually and morally, that is, with the conflation of G-d with truth and of G-d with self-perfection, atheism is a good way to kick over their blocks. “Look at all these arguments that say the truth and the human being are both just fine without G-d.” Thus, the Chassidic Master who said that a Jew ought to be an atheist when their fellow man asks for charity or help. We ought not to say, “G-d will provide for them.” Atheism exists to break through the opacity and coarseness of our representations of G-d.
If their issue is primarily making of G-d a source of blessing and benefit to the human endeavor, idolatry is the temptation: “He exists, I grant, but it doesn’t matter! His benefits are achievable without Him. Why pray when you can work, protest, exercise, or study?” The difficult question for the believer that they ought to ask themselves every night: Is there more to me than there was to Abraham’s father? Would I have seen what my forefather saw?
Finally, if they are not concerned with fitting G-d in their heart but rather hold Him as an intellectual ideal, humanism retorts, “You can be spiritually ordered and complete as G-d would want without G-d needing to actually be there; G-d was the center of your heart all along.” Why do you sit at the Pesach Seder, or light the Chanukah menorah? Are these functionally any different than attending a museum? What makes the Jewish Film Festival Jewish? These, too, can be uncomfortable questions for comfortable Jews.
Traditional religion, in turn, reminds each of these errors that they, too, are errors. It fights atheism’s range of arguments when they wish to end the matter, rebukes idolatrous gnosticism, and rages against humanist myopia.
Meanwhile, the Jew. The Jew belongs to something else, and many sense it. As a perceptive fellow once said, “There is a certain people scattered and separate among the peoples throughout all the provinces of your kingdom, and their laws differ from [those of] every people, and they do not keep the king’s laws; it is [therefore] of no use for the king to let them be.”
The king is no mere drunk historical Persian lecher. The king is The Ruler of All. The problem is, this is a worldly concept, a translation of the truth. When the Torah calls G-d King, it means He is both more a king (in the defined sense of the term) and that He is not a king at all (in that sense). The space of the ark exists to express that there is no space. The center of Judaism is the center because it is not on the map. As ideologies fight and refine themselves upon each other, we remember that they exist for G-d, and not vice versa. So should we exist.