Kohen

Almost every role in this atlas can be entered and left. A priest can be laicised, a bhikkhu can disrobe, a pastor can be voted out, an imam can be dismissed by a mosque committee. The kohen cannot do any of it.

Priestly status in Judaism is a fact about ancestry. It is not conferred, so there is no conferring authority to reverse it. A kohen who abandons observance entirely is still a kohen; his sons are kohanim; his obligations and restrictions remain in force whether or not he keeps them. The law does recognise a chalal, a man of priestly descent disqualified from priestly duties by his father's forbidden marriage, but that is a defect in the line, established at birth, not a punishment anyone administers.

The practical edge of this shows in modern hard cases. A kohen who wishes to marry a divorcee or a convert is refused by the Israeli rabbinate, which controls Jewish marriage in Israel, and the couple's usual recourse is to marry abroad and register the civil marriage on return. Men have sought rabbinic rulings casting doubt on their own priestly descent in order to escape the restriction, and the responsa literature on this is substantial and not sympathetic.

Reform Judaism sets the priestly distinctions aside, on the position that the Temple cult is not to be restored and its class structure need not be maintained. That is a decision about whether the category still means anything, not a mechanism for leaving it.

Priestly status is transmitted from father to son by an unbroken claim of descent from Aaron that Jewish communities have maintained by tradition and by family record for millennia without any central registry, since the priesthood needed no such registry as long as the Temple stood and its personnel were locally known; the claim survived the loss of the Temple as an inherited status even after it lost its original function.

In the 1990s a genetic study of Y-chromosome markers among self-identified kohanim from geographically separated Jewish communities, including Ashkenazi and Sephardi populations that had been apart for many centuries, found a shared genetic signature, later called the Cohen Modal Haplotype, at notably higher frequency among kohanim than among other Jews, a finding read by many as independent evidence for a real shared paternal line, though later research has qualified how precisely it can date or confirm any individual family's claim.

The office remains visible in ordinary religious life: a kohen is called first to the Torah reading in traditional synagogues, and the priestly blessing, Birkat Kohanim, is still recited by kohanim over the congregation on major festivals, drawing especially large gatherings of kohanim performing it together at the Western Wall in Jerusalem during Passover and Sukkot.