Dayan

A dayan serves as a judge on a beth din, a rabbinical court applying Jewish law to matters including conversion to Judaism, the granting of a religious divorce, a get, disputes between Jewish businesses or individuals who choose to submit to rabbinical rather than civil arbitration, and questions of personal status such as confirming Jewish lineage; the qualification for serving as a dayan is considerably more demanding than for ordinary rabbinic ordination, requiring specialized training in the procedural and evidentiary law governing rabbinical courts beyond the general legal and textual mastery ordinary semicha certifies.

A beth din typically sits with three dayanim for most matters, a plurality required under Jewish law for a valid court, and its decisions, while not enforceable through state power in most countries, carry significant religious weight for observant Jews, particularly regarding personal status questions such as a valid religious divorce, without which a Jewish woman is considered unable to remarry within Jewish law regardless of any civil divorce already granted; the resulting cases in which a husband refuses to grant a get, leaving his wife an agunah, a chained woman unable to remarry religiously, have become a significant subject of communal and legal advocacy across the Jewish world.

A functioning beth din normally sits with three dayanim rather than a single judge, a requirement drawn from Jewish law's general preference for a panel over any one person's individual judgment in matters of consequence, though the presiding dayan, often the most senior in scholarship or experience, typically directs proceedings and writes or approves the court's final ruling. Major Jewish communities maintain standing batei din, such as the London Beth Din long associated with the United Kingdom's Chief Rabbinate, that handle recurring categories of case: supervising conversions to Judaism, overseeing religious divorce through the writing and delivery of a get, certifying food and products as kosher, and arbitrating civil disputes that Jewish parties choose to bring before a religious rather than a secular court.

Because a dayan's rulings can have serious practical consequences for the people involved, particularly in divorce and conversion cases where an error can leave a person's marital or religious status genuinely uncertain under Jewish law, the additional ordination of yadin yadin, beyond the ordinary rabbinic semichah, is treated as a serious credential in its own right, and not every ordained rabbi pursues it or is recognized as qualified to sit as a dayan even where he has studied civil law extensively.