Posek

Posek (Hebrew: פוסק‎ [poˈsek], pl. Poskim, פוסקים‎) is the term in Jewish law for "decisor"—a legal scholar who decides the Halakha in cases of law where previous authorities are inconclusive or in those situations where no halakhic precedent exists.

The decision of a posek is known as a psak din or psak halakha ("ruling of law"; pl. piskei din, piskei halakha) or simply a "psak". In Hebrew, פסק is the root implying to "stop" or "cease"—the posek brings the process of legal debate to finality. Piskei din are generally recorded in the responsa literature.

In formulating a ruling, a posek will base the psak din on a careful analysis of the relevant underlying legal principles, as well as a careful study of the application of these principles. A Posek must therefore be thoroughly versed in rabbinic literature, especially the Babylonian Talmud.

The process of analysis usually entails today:

The ruling itself is an attempt to apply the precedents and principles of the Tradition to the question being asked. One common goal of poskim in this regard is, as far as possible, to be consistent with the codified law, as well as with the maximal relevant legal precedents, generally being decisions recorded in the responsa literature.

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