Since we are nearing Holy Week, it seems an appropriate time to talk about the theories of Atonement. It's a big topic, which I cannot possibly give the amount of time it deserves, but maybe I can offer you some thoughts to get your own conversations going.
For starters, let's form the question in a way that everyone, regardless of their theological or biblical background, can engage it. Here's the question: What is the significance of Jesus dying on the cross?
Here's a few background verses from scripture:
Isaiah 53:4-6, 10, 11 - "Surely he has borne our griefs and carried our sorrows; yet we esteemed him stricken, smitten by God, and afflicted. But he was wounded for our transgressions, he was bruised for our iniquities; upon him was the chastisement that made us whole, and with his stripes we are healed. All we like sheep have gone astray; we have turned every one to his own way; and the LORD has laid on him the iniquity of us all [...] It was the will of the LORD to bruise him; he has put him to grief; when he makes himself an offering for sin [...] By his knowledge shall the righteous one, my servant, make many to be accounted righteous; and he shall bear their iniquities."
2 Corinthians 5:21 - "For our sake he made him to be sin who knew no sin, so that in him we might become the righteousness of God."
Galatians 3:10, 13 - "All who rely on works of the law are under a curse; for it is written, 'Cursed be every one who does not abide by all things written in the book of the law, and do them.' [...] Christ redeemed us from the curse of the law, having become a curse for us - for it is written, 'Cursed be every one who hangs on a tree'"
1 Peter 2:24 - "He himself bore our sins in his body on the tree, that we might die to sin and live to righteousness."
1 Peter 3:18 - "For Christ also died for sins once for all, the righteous for the unrighteous, that he might bring us to God"
Isaiah and Paul did not spell out exactly what they meant, which left it up to the early Church to figure out how to explain the cross.
What some claim was first taught was the Ransom Theory, which proposed that Jesus was a ransom paid to Satan to free all of humanity from sin. God tricked Satan, through the resurrection. Some claim (I'm hedging here on purpose; you'll understand why later on) that this was the teaching, with some variations, of Irenaeus, Origen, Gregory of Nyssa, Augustine and Bernard of Clairvaux.
As you can imagine, some folks had some difficulties with this idea. It makes Satan out to be, to some degree, an equal to God, suggesting more than a bit of Dualism. The victory is won through an act of deception by God. Further reading here.
Next came Anselm's Satisfaction Theory, which was similar to the Ransom idea, but the price was paid to God, not Satan. As it arose in the 11th century, it is not surprising that it is somewhat derived from European feudal culture, in which a serf must honor their human lord who owned the land and controlled their lives. It is about honor. Since sin dishonors God, a price must be paid to restore God's honor. This is sometimes spoken of as satisfying the "ethical nature" or "justice" of God. This idea is also connected to the "sin sacrifice" found in the Hebrew scriptures.
Although fitting very well with some of Paul's writings, this theory has been troubling to many people, as it claims God requires a sacrifice for justice to be preserved. Although it removes the Dualism of the Ransom theory, it now depicts God as having some of the questionable qualities previously attributed to Satan. Read more here.
An early objection to Anselm's theory was offered by Peter Abelard, writing in the early 12th century, who is credited with presenting what is now known as the Moral Influence Theory. Basically, this is the idea that the life and death of Jesus Christ serves as a a moral example to us all. Through this example, we are moved to leave our sin and draw closer to God.
One difficulty with this theory is that there is a strong dependence on our own response. It leans very far towards the idea that we can save ourselves. Abelard was condemened as a heretic, by the way. Read more here
In the 16th century, the early reformers, including Luther and Calvin, developed a new twist to the Satisfaction Theory, which is now usually referred to as the Penal Substitution Theory. It is the dominant theory of Atonement among Protestants today. It takes Anselm's idea that God demands satisfaction a step further; insisting that God demands punishment. Read more here. Also, I found this discussion to be very helpful.
One last theory must be mentioned; Christus Victor. In 1931, Gustaf Aulén reintroduced the term. He argues that this was the theology of the atonement of the early Church Fathers, not the Ransom theory. "Ransom” is seen as a rescue or liberation of humanity from the slavery of sin. Some have suggested that this approach to Atonement is much more along the lines of what the Orthodox Church has always taught. It begins with the Incarnation; the Word became flesh and dwelt among us. Death becomes part of the human experience. What has not been assumed has not been redeemed. Read more here.
Now, regarding my personal take. Having come from an Evangelical background, praying before a crucifix was new to me when I arrived at seminary. It is now my preferred setting. When I gaze upon the cross, I find myself powerfully moved. Sometimes it is simply the story of the Passion that evokes such strong emotions. Other times it is from remembering that God is not indifferent to human suffering, having experienced it. Sometimes it is from being reminded that I cannot be indifferent either. Recalling the suffering of those who are around me when before the cross leads to heartfelt intercessory prayer.
If you wanted something definitive regarding Atonement, sorry to disappoint you. Personally, I don't think there is one right answer. But I do agree with this segment of C. S. Lewis' opinion of the matter:
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...J.