The notion that an angry God demanded a blood sacrifice from his only Son to appease his wrath toward humanity is a foreign concept among the Fathers and Catholic theologians. “Atonement” in the broadest sense means to reconcile or to make one. It has taken on a narrower meaning in theology to denote the satisfaction of an offense or injury against God.
It is humanity that has committed the offense against God. That offense is sin, and some satisfaction must be offered in order to reconcile humanity with God to make them one again. The problem is that the offense of sin against God is too great for humanity to repair on its own. In other words, humanity alone is unable to atone for the injustice it has committed (and will commit) against God.
St. Anselm is credited with developing from the the patristic writings and scripture the concept of “vicarious atonement.” Since humanity is unable alone to satisfy the offense of sin, God became man through the Incarnation. This one man (Jesus), who is also God, is the only person who can make the perfect satisfaction for humanity’s sins. That satisfaction consists of his complete obedience to God, obedience unto death on the cross.
Peter Abelard later expanded and clarified St. Anselm’s teachings into what today has become a primary basis for most modern Catholic teaching on the atonement. The Catholic Encyclopedia states it best here: “And, in his view, the reason for the Incarnation and the death of Christ was the pure love of God. By no other means could men be so effectually turned from sin and moved to love God.”
It is Abelard then who finally placed the focus on God’s love for humanity above all other things. Man has willingly sinned, has chosen to separate himself from God. In order to turn man back to God, to allow humanity to be one with Him, God became man and gave humanity the perfect example of obedience to follow - his Son Jesus.
Rather than a God who sacrificed his own Son out of wrath to satisfy his own anger, it is a God who out of his infinite love for humanity showed us the way to come back to him; so that we can be reconciled and become one with Him. Abelard and later Aquinas came to the remarkable conclusion that Jesus’ vicarious atonement was more than necessary to satisfy the offense of sin. Nevertheless, God chose to experience death on the cross to show his superabundance of love for us and the way to our own salvation.