People often have a tendency to think linearly: to assign a numeric value, for example, to a qualitative value. Think of the descriptors: “the best doctor,” “the best dancer,” or any other. In actuality, when describing different colors, it is almost entirely meaningless to understand the color “red” or “green” in terms of what percentage of black or white they may be.
The same is true for relationships, and for the laws that govern those relationships. Though there is no denying that some marriages are better than others, it would be silly to say that a particular couple has the best marriage. Nobody in their right mind would really want to be in someone else’s marriage; each of us necessarily has our own inputs into a relationship that makes it work (or not) for us as individuals.
By the same token, it is not accurate to suggest that priests, Cohenim, are more holy than ordinary people. But it would be right to suggest that their proximity to the mishkan, the tabernacle, means that they have a different kind of relationship with G-d. Cohenim are, for example, less free than other Jews to serve G-d through creativity and improvisation. And they have a different set of rules than those which govern other Jews.
Among those rules are those dealing with marriage. A normal Cohen could marry a widow, but not a divorcee. And the Cohen Gadol, the High Priest, was forbidden from even marrying a woman who had even ever intimately known another man. Many people mistakenly conclude that virgins are superior, or that these laws explain how Cohenim are more holy than are other Jews.
But this is a misunderstanding. We don’t celebrate virgins. Indeed, Judaism is all about intimacy between man and wife, mankind and G-d. Men are meant to desire their wives in an ongoing intimate relationship, because a marriage is a much deeper and more developed thing than a mere wedding. So why does G-d require that the Cohen Gadol marries a virgin, a woman who has never loved any other man?
We must remember that all marriages are reflections of our respective marriages with G-d. Tip O’Neill (not a man frequently quoted in words of Torah) said that, “All politics is local.” He could well have been channeling the Torah, for whom the message is that “all religion is personal.” Yes: G-d is the King of Kings, and the creator of the world. But we relate to Hashem through our personal marriages. We are inspired to holiness in our relationship with G-d, through the pursuit of holiness in our relationship with our spouses.
And the Cohen Gadol had a qualitatively different relationship with G-d than does another Jews. The Cohen Gadol served in the Mishkan, the place where the divine presence, the shechinah dwells (mishkan and shechniah share a root). The shechinah is different from the other attributes of G-d who are available to the world: the shechinah is precisely like a woman who has only ever known her husband: the shechinah is the aspect of Hashem that has never loved anyone else.
A man, in Biblical Judaism, is allowed many wives. And so it should not surprise us that Hashem has relationships and involvements with many different nations. The Torah itself tells us that certain lands are not for the Jews, because they are reserved for other nations. And we certainly believe that G-d can be involved in the events of this world, even the ones that may not directly affect Jews.
And so, too, the male aspects of G-d, especially Elokim, have been known to the world ever since G-d revealed himself as Elokim to the Egyptians. G-d touches many people, not just Jews. The Torah does not pretend otherwise: G-d talks to non-Jews, and he even prophesies through people like Bilaam.
But the female aspect of Hashem is not like the male aspects. Unlike a man who is out in the world interacting in the public square, the classic Torah woman is someone who creates a home, an environment of love and nurturing, of specialness and intimacy. And while women may well be divorced, or have known many men, the Cohen Gadol needs to see his marriage as the mirror image of his relationship with the shechinah (the name of Hashem that is in the feminine form) – and so he can only be married to a woman who, just like the aspect of G-d that he knows, has never loved any other people, has never been intimate with another man.
A regular Cohen can marry a widow, but not a divorcé. I would see this as a reflection of the fact that while G-d “dwells” in the Beis Hamikdash and the Mishkan, he is most intensely found in the holy-of-holies, the place that only the Cohen Gadol goes. A regular Cohen may not be as close to the shechinah, but he, too, must understand through his terrestrial relationship with a woman who never ended a relationship with a man, that G-d has never, and will never, end His relationship with us.
P.S. To be true, the Gemara tells us of many ways in which we, too, can interact with the shechinah – and our marriages are not exclusively to virgins. But unlike the Cohen Gadol, this interaction is voluntary, and on a case-by-case basis. This may be a spiritual reason why men prefer to marry a woman who has not known other men; it may enable access to facets of a relationship with G-d that are not available to a man who marries a divorcé.