To be sure, some of these inmates have committed unthinkably hideous crimes. Stephen Michael West, the man who was executed Thursday night, was on death row for raping and murdering 15-year-old Sheila Romines in 1986, and for murdering her mother, Wanda. Both were found dead of stab wounds that suggested they had been tortured, probably for hours, before they finally bled out. The story of their suffering is unbearable to read. Sheila Romines knew Ronnie Martin, the co-defendant in the crime, from school. He was 17.

Mr. West admitted to the rape but denied murdering either woman. His attorneys said he was paralyzed in the face of his accomplice’s brutality because he suffered from severe schizophrenia and post-traumatic stress disorder, the result of profound abuse as a child. At his trial, jurors were never told of his mental illness.

There is nothing about Mr. West’s case that would move staunch supporters of the death penalty to rethink their position, but the reasons for ending state-sanctioned murder are manifold: It fails to deter crime; it is far more expensive than life in prison without parole; it is racially biased. Perhaps most tellingly, death sentences are too often dealt to innocent people. Any one of those reasons, by itself, makes a compelling argument for ending executions altogether.

Even among the indisputably guilty, extenuating circumstances often cloud the issue. Is it right to execute an inmate who has been rehabilitated and displays sincere remorse? An inmate with dementia who no longer remembers his crime? An inmate whose mental illness is now being successfully treated? People who knew Mr. West said he had become a different man, and isn’t true rehabilitation justification enough for commuting a sentence to life without parole? As Tennesseans for Alternatives to the Death Penalty tweeted a few days before the execution, “When an inmate’s severe mental illness is undisputed by the state’s own doctors, what does it take to show that life without parole is the appropriate sentence?”

But my own reason for wanting to end the death penalty is simpler than any of these arguments, as compelling as they truly are. As a Christian, I keep coming back to exhortations like “Thou shalt not kill” and “He that is without sin among you, let him first cast a stone” and “Blessed are the merciful, for they will be shown mercy.” It seems to me that Jesus was very clear on this question of mercy. At his own execution, he prayed, “Father forgive them, they know not what they do.”