Cardinal Walter Kasper has tried to address the controversy over some interpretations of Pope Francis’ exhortation Amoris Laetitia, but one theologian has said his theological language could be confusing to Catholics.

In an interview this week with Vatican News, Cardinal Kasper explicitly addressed Footnote 351 of the Pope’s apostolic exhortation, which discusses admission to the sacraments of the divorced and remarried. The cardinal said that the footnote should be read in light of the sixteenth century Council of Trent’s decree on the Eucharist.

“The Council of Trent says that in the case in which there is no grave sin, but venial, the Eucharist removes that sin,” the cardinal said, adding “Sin is a complex term. It not only includes an objective principle, but there is also the intention, the person’s conscience. And this needs to be examined in the internal forum—in the Sacrament of Reconciliation—if there is truly a grave sin, or perhaps a venial sin, or perhaps nothing.”

“If it is only a venial sin, the person can be absolved and admitted to the Sacrament of the Eucharist,” the cardinal continued. “This already corresponds with the doctrine of Pope John Paul II and, in this sense, Pope Francis is in complete continuity with the direction opened by preceding popes.”

“I do not see any reason, then, to say that this is a heresy,” he said.

Kevin Miller, a theology professor at Franciscan University of Steubenville, was critical of the cardinal’s language on sin: “at best it’s a bit theologically sloppy and potentially confusing.”

“He seems to be using ‘grave sin’ as a synonym or substitute for ‘mortal sin’,” Miller told CNA.

Mortal sins consist of “a grave matter, done knowingly and freely.” Sins that don’t involve grave matter, or do but lack “the requisite degree of knowledge and freedom” are venial.

Miller said he disliked the language of “grave sin” because it has been associated with the “fundamental option” theory of sin that he says “in essence redefines the ‘freedom’ needed for mortal sin — on (supposed) theological grounds — so that it becomes much more difficult to commit a mortal sin than the doctrinal and theological tradition has generally understood.” This approach is rejected in places such as St. John Paul II’s 1993 encyclical Veritatis Splendor.

While Miller said he is not asserting that Cardinal Kasper accepts this theory, the cardinal’s words run “substantial risk of producing confusion” among those who might.

There could also be confusion about freedom and what is necessary for repentance and absolution, he said, taking as an example a cohabiting partner who feels “significant psychological pressure” to remain in a relationship lest the other partner leave and deprive children of a parent or parental figure.

“This kind of psychological pressure could affect the person’s freedom and therefore the nature of the sin the person is committing,” Miller said. “But repentance (and therefore absolution) requires, I think, that the person (probably typically the woman) be doing something genuinely sincere, and concrete or specific or practical to formulate an ‘out’ to the situation.”

This attempt to change the situation includes accepting “the reality that a (maybe) good end doesn’t justify an evil means,” he said, adding “One can’t simply say that as long as the pressure continues, the lack of freedom necessary for mortal sin continues.”

While there may be cases in which cohabitation is a venial sin, the professor continued, it is “always grave matter.”

“It could in some cases not be accompanied by sufficient knowledge and/or freedom to make it a mortal sin,” Miller acknowledged. But even so, it is a separate question whether defenders of the controversial interpretations of Amoris Laetitia have made a good case about what circumstances “would in fact amount to a lack of sufficient freedom.”

Cardinal Kasper’s interview reflected on the results where some parishes have meetings with spouses or engaged couples in which they read part of Amoris Laetitia.

“This document’s language is so clear that any Christian can understand it,” the cardinal said. “It is not high theology incomprehensible to people. The People of God are very content, and happy with this document because it gives space to freedom, but it also interprets the substance of the Christian message in an understandable language.”

He said this shows “the Pope has an optimal connection with the People of God”

Cardinal Kasper’s remarks also reflected on the importance of mercy.

“Today we are living a violent time which has never before been experienced,” he said. “Many people are wounded. Even in marriages there are many who are wounded. People need mercy, empathy, the sympathy of the Church in these difficult times in which we are living today. I think that mercy is the response to the signs of our times.”

Miller found truth in these comments.

“St. John Paul II spoke of mercy as the limit God puts on evil,” he said. However, the professor suggested there is a “more complex” relationship between mercy and empathy.

“For the Church, there is not even tension, let alone opposition, between mercy and truth each authentically understood,” Miller said. “Mercy, insofar as it is a reality in God’s saving plan, is part of the truth. Truth, insofar as it sets us free for sharing in God’s life and happiness, is mercy.”

There are ways of presenting truth that are more or less merciful, he noted, adding “But withholding the truth about God’s loving and transformative grace and law is not merciful either.”

Cardinal Kasper’s interview reflected on the necessary role for debate in the Church.

“There is no need to fear debate!” he said. However, there is now “a very bitter debate, way too strong, with accusations of heresy.”

“A heresy is a tenacious disagreement with formal dogma,” he said. “The doctrine of the indissolubility of marriage has not been called into question on Pope Francis’ part!”

The cardinal said that before any such accusation of heresy, “the question should be what the other person means by what has been said.”

“And, above all, that the other person is Catholic should be presupposed, the opposite should not be supposed!” he emphasized, in an English-language translation of the Vatican News interview.

Vatican News reported the Kasper interview in several languages, while also posting audio interviews with the cardinal in different languages. Some audio versions include comments expanded beyond the reported text.

Cardinal Kasper is President Emeritus of the Pontifical Council for Promoting Christian Unity. He was joined in Rome by Archbishop Vincenzo Paglia, President of the Pontifical Academy of Life, to present the cardinal’s new book, “Amoris Laetitia’s Message: A Brotherly Discussion.”