The theologian said that, while the Pope's term "inadmissible" was ambiguous - and thus not necessarily in contradiction with Church teaching - it would be widely interpreted as meaning "intrinsically immoral", which would contradict Catholic doctrine.
But it went on: "Today, however, there is an increasing awareness that the dignity of the person is not lost even after the commission of very serious crimes".
It also argues that today's more effective detention methods protect citizens and "do not definitively deprive the guilty of the possibility of redemption".
As part of the revision, Francis called on the church to recommit itself to working with civil authorities to eliminate the death penalty where it is still used as a deterrent to crime.
In the past, the Catechism of the Catholic Church has supported the death penalty "if this is the only possible way of effectively defending human lives against the unjust aggressor". It stated it was "the well-founded right and duty of legitimate public authority to punish malefactors by means of penalties commensurate with the gravity of the crime, not excluding, in cases of extreme gravity, the death penalty".More news: National Archives may not finish reviewing Kavanaugh documents before end of October
But on Thursday he went further by making a formal change to the universal catechism, or church teaching.
Several capital punishment proposals for different crimes are pending in the Senate, but discussions on these were not prioritized.
Significantly, the amended text does not state that capital punishment is intrinsically evil, calling it instead "inadmissible", while referring to changed circumstances that would make it so in the current social context.
Pope Francis addresses his weekly audience in Saint Peter's square at the Vatican on June 6, 2018. The church had for centuries permitted executions, but in 1997, John Paul II dramatically narrowed the standards for when the punishment was permissible.More news: Fed leaves key rate unchanged with U.S. economy growing at 'strong rate'
"Evangelium Vitae" ("The Gospel of Life") was St. John Paul's 1995 encyclical letter on the dignity and sacredness of all human life. "He had a document, 'The Gospel of Life, ' in which he said it is essentially the conditions (that) were once considered OK for allowing the death penalty have basically disappeared".
"Who are we to take away the life of other people?"
More than 80 percent of the 993 executions recorded in 2017 by Amnesty International were carried out in the Arab world - led by Iran, Saudi Arabia and Iraq. "For believers, either the Big Man calls the shots of who lives and who dies, or we do - which is it?"
The primary responsibility of the public authority has always been to protect the common good, the letter states, but the death penalty emerged from an environment "in which it was more hard to guarantee that the criminal could not repeat his crime".
More than two-thirds of countries - including most predominantly Catholic states - have abolished or suspended judicial killings.More news: Malaysia's civil aviation chief resigns over MH370 failures