Mercy seat

According to the Hebrew Bible, the mercy seat (Hebrew: הַכַּפֹּֽרֶת‎‎ ha-kappōreṯ) was the gold lid with two cherubim beaten out of the ends of it to form a covering over this gold lid and placed on the Ark of the Covenant. This was connected with the rituals of the Day of Atonement; where God did appear. The term also appears in later Jewish sources, and twice in the New Testament, from where it has significance in Christian theology.

The English phrase mercy seat is a translation of the Hebrew kapporeth (in the Masoretic text) and Greek ἱλαστήριον (hilasterion; in the Septuagint) by William Tyndale influenced by the German word Gnadenstuhl as in the Luther Bible; Gnadenstuhl, literally meaning seat of grace.

Though kapporeth is probably derived from kaphar, which is often considered to mean cover, the literal meaning of kaphar is wipe out, implying that kapporeth means thing of wiping out/thing of cleansing. The cognate Arabic term كَفَرَتْ kaffarat (also generally taken to mean cover, but from which the word kafir also derives) is used in modern legal contexts to refer to any mechanism of rectifying illegality (ranging from rectifying the failure to fast during Ramadan to the rectification of murder), for example the freeing of a slave after the slave has suffered shocking circumstances could be considered as a kaffarat. Similarly, hilasterion etymologically means thing for propitiation, with Hesychius writing that a synonym of hilasterion was thing for catharsis, while the Vulgate translates it as propitiatorium. Thus it is unclear whether the kapporeth was the lid of the Ark, or merely sat on top of the Ark, possibly with the Ark having a cover beneath it.

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