In Cur Deus Homo (Why God man?), Anselm seeks to understand the divine logic of the atonement. He is concerned about utilizing tools of logic and learning to articulate his faith, “I do not seek to understand in order that I may believe, but I believe in order to understand.”
A summary of Anselm’s argument in Cur Deus Homo
(a) The human race has offended God’s honor and therefore has incurred an infinite debt
(b) It would be unfitting and unjust for God to accept humans as they are
(c) Redemption requires repaying the infinite debt, which fallen humanity cannot do
(d) It is unfitting that no human being should attain the goal for which humanity was created. Otherwise God would have pointlessly created humanity
(e) Therefore, in creating humanity, God freely obligated himself to complete his work in humanity
(f) Only God can repay the debt, humanity ought to repay it; therefore the one who does it must be both divine and human (that is, a God-man).
(g) In order to redeem those who fell through Adam’s sin, the God-man must be a descendant of Adam, not a new sort of creature or a human from another “race.”
(h) Since the God-man is a good greater than the evil of all sins, his voluntary death can make recompense for all sins if it is given for their remission
Biblical Material in support of the Satisfaction Theory (Sampling)
(i) Isaiah 53:5 (ii) Mark 10:45 (iii) John 1:29 (iv) I Peter 2:24 (v) I John 2:2 (vi) Isaiah 53:10 (vii) Col. 1:19-20 (viii) Isaiah 53:6 (ix) Mark 10:45 (x) II Cor 5:21
Note: taken from Doctrine II handouts 2009 – “The Nature and Extent of the Atonement” by D. Felch.