Sin is man's basic problem. It displeases God and causes the fellowship between man and God to be broken. In other words, sin separates us from our Creator. Religion, however, can provide a solution to this problem. Jesus Christ obediently and lovingly died on the cross that our sins might be forgiven through His blood (Matt. 26:28). In other words, He made the removal of the sin barrier possible at Calvary. He made it possible for our sins to be cleansed. The restoration of fellowship between God and man is what atonement is all about.
Atonement is a difficult word to adequately define. All of the following concepts are related to it to varying degrees: to cover, to expiate, to appease, to propitiate, and to reconcile. Some have simply stated that atonement is to be at one with God (i.e., at peace and in full fellowship with Him). When atonement is realized, one's sins are covered, God's wrath is appeased, and reconciliation is achieved. What a glorious thought! It is in Christ's shed blood where the power of atonement lies. God set Jesus forth "as a propitiation [or mercy seat] by His blood, through faith..." (Rom. 3:25; cf. Exo. 25:21,22; Lev. 16). The obedient faith of man, combined with the blood of the Christ, makes atonement possible.
It is important for Christians to understand the basic idea of atonement. The Bible addresses the theme in several places and always relates it to sacrifice (ultimately, Jesus' sacrifice). However, a systematic explanation of why Jesus had to die is not given. We know, of course, that His love motivated His obedience and that it was the Father's will that atonement become a reality through the cross, but, even with that knowledge, there are unanswered questions.
Because of these questions, a number of theories on the atonement have been advanced by Christians to explain how and why redemption is made possible through the life, death, and resurrection of Jesus Christ. Concerning these theories, their usefulness, and their role, C.S. Lewis wrote in the fourth chapter of Mere Christianity:
"We are told that Christ was killed for us, that His death has washed out our sins, and that by dying He disabled death itself. That is the formula. That is Christianity. That is what has to be believed. Any theories we build up as to how Christ's death did all this are, in my view, quite secondary: mere plans or diagrams to be left alone if they do not help us, and, even if they do help us, not to be confused with the thing itself. All the same, some of these theories are worth looking at."
I believe Lewis approached this subject with wisdom. We must not allow ourselves to be led away from the truth by the theories of men, but there is no harm in investigating various theories that seek to explain difficult aspects and questions related to various Bible topics. That is what we will endeavor to do as we study the subject of atonement over the next four lessons. Each of these lessons will focus on one basic theory of atonement; that is, one basic rationale as to why Jesus had to die and how His death makes atonement possible. Each theory will be presented with an illustration to help explain it and enable us to more fully relate to it and remember it. A significant point to be mindful of throughout this series of lessons is that these are merely theories of men, and they all seem to fall short in one or more aspects. Nevertheless, considering their strengths and weaknesses is helpful for Christians endeavoring to better understand what the Bible teaches about atonement. If these lessons enable you to better understand the significance of Jesus' death and more fully appreciate His sacrificial love, then our time spent on this fascinating subject will be well spent.