The English word 'atonement' (uh tohne' mehnt), originally meant "at-one-ment", i.e. being "at one", in harmony, with someone.1 Meaning reconciliation, it was associated with sacrificial offerings to remove the effects of sin.
We must understand that God hates sin. God is perfectly holy and just, He cannot tolerate sin. Sin is the things that humans do to break God’s law and is the opposite of His holiness. God and sin cannot co-exist (Exodus 34:7b). God’s law is representative of His holy and perfect nature. When humans break God’s law, they are sinning. Like any other law there is a price to pay for breaking the law. Someone caught breaking the speed limit will usually get a ticket or have their license taken away. The Bible says that the price of breaking God’s law (sinning) is death (Rom. 6:23a, Ez. 18:20). Man has become God’s enemies and is deserving of God’s anger and punishment. That is where atonement comes in. God is Love and He loves the people He created. He loved humanity enough that, though humanity did not deserve it, He chose to provide a way to save us from the punishment that was deserved. God created a process to save man from their sin, that process is called atonement.
Primarily in the Old Testament, atonement most frequently refers to humans offering sacrifices to God for their sins, it is the process God established whereby humans could make an offering to God to restore fellowship with God. 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 Atonement 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