One of the most precious doctrines of the Christian faith is that of atonement. Some of us will remember learning as children in Sunday School the simple definition that comes from dividing the syllables of the word to spell “at-one-ment.” Our sins have separated us from God, placing us under His wrath and curse, and making us His enemies. But by His sacrificial death for us on the cross, Jesus has taken that curse on Himself and removed the barrier between us and the Father. Apart from His work, we would have been permanently barred from God’s presence and favor, but now by His atonement we are permanently and graciously “at one” with Him.
This is not a doctrine unique to the New Testament. It has its origins in the earliest chapters of the Bible where Adam and Eve’s sin cut them off from God’s presence, resulting in their being driven from the Garden of Eden. But God’s grace was evident from the very beginning of human history as God Himself provided a substitute as He took the life of an animal, shedding its blood, to make atonement for them, a covering for them in their physical nakedness, symbolizing His providing a covering for their spiritual nakedness.
And in an even more dramatic way, God enshrined this principle in the Mosaic sacrificial and ceremonial system with the provisions for observing the annual Yom Kippur, the Day of Atonement (literally the day of covering) for the people of Israel, described in Leviticus 16. The two major sacrifices on that day taught His people about the parallel dimensions of expiation and propitiation. The sins of the people were understood to be transferred to these substitutes. In the first, what we remember as the “scapegoat” was led far out into the wilderness where it could never return. This taught them that their sins were removed “as far as the east is from the west” (Psalm 103:12), never to be remembered against them (Hebrews 8:12). This was the expiation side of atonement. In the second, with their sins once again transferred to the animal substitute, its blood was shed as it was killed, thus demonstrating that God’s justice was satisfied. This was the propitiation side of atonement.