Who taught it?
Faustus and Laelius Socinus (1539-1604) founded the Socinians, who taught the Moral Example theory. This view is still very influential in Unitarian circles today. Socinus was an Italian theologian, who lived in Poland after 1578, and he garnered a rather large following.
What does it teach?
This view teaches that the Cross gives us a perfect example of how to obey God.
Which passages support it?
Advocates of this view point to 1 Peter 2:21, which states: “For you have been called for this purpose, since Christ also suffered for you, leaving you an example for you to follow in His steps.” Likewise, Jesus commanded, “If anyone wishes to come after Me, he must deny himself, and take up his cross daily and follow Me” (Lk. 9:23).
Criticism of this view?
We don’t believe that this view is wrong. Certainly we are to be imitators of Christ, and the Cross was the perfect expression of obedience to God. However, we deny that this was the central reason why Christ had to die: why would God ask Christ to go through this suffering for us to follow? There must be a sufficient purpose for God to incarnate and die in this way. Substitutionary atonement satisfies this purpose, but the example theory is left wanting. Once we affirm substitutionary atonement, the example theory makes more sense. We should suffer for a purpose that is far beyond our understanding (Rom. 8:28), the way that Christ did (Heb. 12:2).
Of course, the Socinians—the founders of this view—believed that Jesus’ death was merely an example, and Jesus was merely a human being—not divine, which we believe is false. They also affirmed Pelagianism, which is the view that humans can seek after God and come into a relationship on their own volition. Erickson writes,
All that is necessary, according to [the Socinians], for God and a human to have fellowship is that the human have faith in and love for God. For God to have required something more would have been contrary to his nature, and to have punished the innocent (Jesus) in place of the guilty would have been contrary to justice.
We believe this theory of the atonement falls very short.
 Erickson, Millard J. Christian Theology: Second Edition. Grand Rapids, MI. Baker Books. 1998. 802.