Jay Parini, a poet and novelist, teaches at Middlebury College. His most recent book is "The Way of Jesus: Living a Spiritual and Ethical Life." The views expressed in this commentary are his own. View more opinion articles on CNN.

(CNN) Pope Francis, who has caused the heads of right-wing Catholics to swivel before, has done it again, proclaiming that the death penalty is inadmissible in all cases "because it is an attack on the inviolability and dignity of the person." He also said that Christians should work "with determination" for the abolition of the death penalty worldwide.

Jay Parini

Good for him, and good for the teachings of Jesus in this important regard, which have been wildly neglected, particularly by Christians in the United States.

Jesus, in the Sermon on the Mount, was absolutely clear about vengeful justice. He summoned the Old Testament teaching of "an eye for an eye, and a tooth for a tooth," and then overturned it sharply. "But I say to you, do not resist evil; but if anyone should strike you, turn the other cheek." Then he went further: "Love your enemies, bless those who curse you, do good for those who hate you, and pray for those who abuse you."

He didn't say: "Kill those who kill people." He said that we should not even "curse" anyone who acted badly, lest we bring judgment upon ourselves.

As ever, the apostle Paul expanded on and clarified the teachings of Jesus in interesting ways. Consider Romans 12:17: "Do not repay anyone evil for evil." A few verses later, he adds: "Do not be overcome by evil, but overcome evil with good."

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