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Study Dictionary
Expiation
NET Glossary: the act of making atonement for sin, or the means by which atonement for sin is made; the term "expiation" is sometimes used in modern English Bible translations as a substitute for the term "propitiation" (e.g.,
Expiation [EBD]
Guilt is said to be expiated when it is visited with punishment falling on a substitute. Expiation is made for our sins when they are punished not in ourselves but in another who consents to stand in our room. It is that by which reconciliation is effected. Sin is thus said to be "covered" by vicarious satisfaction.
The cover or lid of the ark is termed in the LXX. hilasterion, that which covered or shut out the claims and demands of the law against the sins of God's people, whereby he became "propitious" to them.
The idea of vicarious expiation runs through the whole Old Testament system of sacrifices. (See PROPITIATION.)
EXPIATION [ISBE]
EXPIATION - eks-pi-a'-shun: This word represents no Hebrew or Greek word not rendered also by "atonement." In Nu 8:7 it is employed in the Revised Version (British and American) to translate chaTath and in Dt 32:43, kipper. This version also employs "expiate" in the margin of several passages, e.g. Ps 65:3; 79:9. Always its use in English Versions of the Bible is somewhat more narrow and specific than "atonement" and has especial reference to specific uncleanness or sin. It will be sufficient to refer to ATONEMENT; SACRIFICE; PROPITIATION.
Also see definition of "Expiation" in Word Study