ιλαστηριον , propitiatory. This word is properly an adjective, agreeing with επιθεμα , a lid, understood, which is expressed by the LXX, Exodus 25:17 . In that version, ιλαστηριον generally answers to the Hebrew כפרת , from the verb כפר , to cover, expiate, and was the lid or covering of the ark of the covenant, made of pure gold, on and before which the high priest was to sprinkle the blood of the expiatory sacrifices on the great day of atonement, and where God promised to meet his people, Exodus 25:17; Exodus 25:22; Exodus 29:42; Exodus 30:36; Leviticus 16:2; Leviticus 16:14 . St. Paul, by applying this name to Christ, Romans 3:25 , assures us that he is the true mercy seat, the reality of what the כפרת represented to the ancient believers; by him our sins are covered or expiated, and through him God communes with us in mercy. The mercy seat also represents our approach to God through Christ; we come to the "throne of grace;" which is only a variation of the term "mercy seat."