Packer calls propitiation “the heart of the Christian gospel.” Our God does not ask us for a sacrifice to appease His holy wrath. Instead of demanding our child, like Artemis, He offers His Son. Jesus is our propitiation. He is the perfect once and for all sacrifice, and the fulfillment of all the sacrifices offered in the temple. On the cross, He absorbed the wrath of God in our place so that our sins may be removed from us. His sacrifice is all-sufficient.
During the mythical Trojan War, the goddess Artemis punished Agamemnon, the Greek general, for evil deeds his soldiers committed. On their way to the war, Artemis caused the winds to stir and their ships were knocked violently into one another. Agamemnon learned that the only way to appease the wrath of Artemis was to sacrifice his daughter to her, so he sent for his daughter and sacrificed her to the goddess. With the anger of the goddess quenched, the ships reached Troy without any more difficulty. The Trojan War legend was written about 1000 years before Christ was born, and it shows that people throughout history, even those who believed in multiple gods, had a sense that their sins must be dealt with, that the wrath of the gods must be satisfied.
Unlike the gods depicted in Greek mythology, our God alone rules and reigns. There is no deficiency in His character, no need for another god. He is the Lord, and He will share His glory with no one. Because He is holy and righteous, His wrath burns against sin. His wrath must be quenched, must be satisfied.
The word used in the New Testament to capture God’s wrath being satisfied is “propitiation.” In Jesus’ story of the Pharisee and the tax collector, the tax collector uses the word, which is often translated “be merciful to me” or “turn your wrath from me” as he recognizes his sinfulness and pleads for mercy (Luke 18:13). The Pharisee thanks God that he is not like others, even the tax collector, and rejoices in his own goodness, the things he does for God. Jesus says that the tax collector, not the Pharisee, goes home justified.