ACTS OF ATONEMENT
Meaning reconciliation, was associated with sacrificial offerings to remove the effects of sin, and in the New Testament, refers specifically to the reconciliation between God and humanity, effected by the death, burial, and resurrection of Jesus Christ.
In the Old Testament atonement refers to the process God established whereby humans could make an offering to God to restore fellowship with Him. Such offerings, including both live and dead animals, incense, and money, were required to remove the bad effects of human sin.
The only fast day stipulated in the Mosaic law was the annual day of Atonement (Yom Kippur), observed on the tenth day of Tishri (September - October) at the conclusion of ten days of penitence. The day of 'Atonemant' was the only day of the year that the priest entered the Holy of Holies to make sin offerings for himself, his family, and the "assembly of Israel." After making these offerings, the nation's sins were symbolically laid on the scapegoat "Azazel" that was released into the wilderness to die.
Most Old Testament scripture, concerning atonement, refers to humans offering sacrifices to God for their wrongdoing. But there are several references of God making atonement. In Psalm 78:38, the Hebrew for "atoned for" is used where the KJV translates "forgave" as is also true in Deuteronomy 21:8.
The New Testament rarely uses a word for atonement. The most common Greek word used is katallasso, usually translated "to reconcile," and the corresponding noun, katallage, meaning "reconciliation." The basic meaning is to establish friendship. This is used in human relationships in I Corinthians 7:11, referring to the restoration of relationship between an estranged husband and wife.
Though atonement is focused in the cross, the New Testament makes clear that Christ's death is the climax of His perfect obedience. He "became obedient unto death, even the death of the cross." Phil. 2:8 Divine love is not sentimental or merely emotional. It is a righteous love which blazes out against all that opposes God's will. God is love (I John 4:8), God is a consuming fire (Hebrew 12:29).
Thus, the cross is simultaneously a manifestation of God's will to save, and of His wrath against sin.