The editor of a high-profile book on marriage said that adhering to Christ's Gospel teachings on divorce is not harsh and mean-spirited, but rather a form of tough love aimed at the salvation of souls.

"Mercy and truth and justice have to accord with one another," said Fr. Robert Dodaro OSA, president of Rome's Patristic Institute, the "Augustinianum," as well as a specialist in patristics and a consultor to the Congregation for the Doctrine of Faith.

Fr. Dodaro is the editor of "Remaining in the Truth of Christ: Marriage and Communion in the Catholic Church," being published shortly before the Oct. 5-19 Synod on the Family, which will gather bishops from around the world to Rome, where they will discuss pastoral solutions to challenges facing the family.

The book includes contributions from nine scholars – including five cardinals – who present the biblical foundation and history behind the Church's long-standing teaching on the indissolubility of marriage.

The subject has become a matter of heated speculation leading up to the synod, after German Cardinal Walter Kasper suggested in February that the Church should reconsider its teaching on divorce, remarriage and Communion.

Fr. Dodaro told CNA Sept. 29 that he shares some of Cardinal Kasper's concerns.

"We would like to see the Church more active in welcoming, embracing, involving divorced and civilly remarried Catholics into the full life of the Church," he explained. "Where we disagree with Cardinal Kasper is on one point, but it is an important one. The question of admission to the sacraments of penance and Holy Communion."

As a solution to the problematic situation, Cardinal Kasper has proposed "oikonomia" – a notion prevalent in Eastern Orthodox Churches. The cardinal has suggested that the Catholic Church follow the Orthodox example of "tolerating, but not accepting second marriages," Fr. Dodaro explained. "We oppose that suggestion."

As the book points out, the Orthodox Church does not have a unified view on the subject.

"There is no single Orthodox position on divorce, on second marriages, on admission to the sacraments; there is no one position that characterizes the views of all of the various Orthodox Churches," Fr. Dodaro explained.

"I have not heard any senior Orthodox prelates applauding the Catholic Church for wanting to adopt or even to look more closely at their practice, so I do not know how much our doing so would contribute to ecumenical dialogue," he added.

Ultimately, the priest discarded "oikonomia" as a valid solution: "We believe that it violates the principle of indissolubility of marriage, because the individuals in question are already married, or at least one of them is. Not just in the eyes of the Church, but in the eyes of Christ. We cannot understand how Cardinal Kasper does not see that."

Fr. Dodaro suggested that the teaching of the indissolubility of marriage would be in danger, especially in marriage preparation, should Cardinal Kasper's proposal be accepted.

"So the priest says to a young couple in marriage preparation that the marriage is 'until death does us part.' They would reply: 'Yes, Father, yes, Father, we get that.' Then after the class, when they leave the rectory, they will say: 'Ok, mom and dad are divorced and remarried and they go to Communion every Sunday, so what's the big deal?'"

A change in the discipline of the Church would introduce confusion about the nature of sin and repentance, he said.

"Let's be clear, we are all sinners, we are not singling out the civilly remarried because they sin. We all sin. Catholics who sin can go to confession and be absolved because they repent of their sin and resolve not to sin again. However, Cardinal Kasper's proposal would allow civilly remarried Catholics to receive sacramental absolution without resolving to cease having sexual relations, while in the eyes of Christ, they are still married to their original spouses. That is what makes the sacrament of penance impossible for them," explains Fr. Dodaro.

Cardinal Kasper recently warned against a "rigid" view and stated in an interview that the Gospel is not a "code of penal law," a phrasing that caught Fr. Dodaro's attention.  

"I agree with the Cardinal that the Gospel is not a code of penal law. But it is a code of divine law and we have to make a distinction between human laws, the laws that the Church makes up, and laws that are divine."

 "When Jesus unveiled his teaching on marriage in the Gospels, he triggered incredulity on the part of his disciples. He told them that Moses had permitted divorce because of the hardness of their hearts, adding, 'but I say to you, in the beginning it was not so.' This is found in Matthew 19. And then Jesus refers the disciples to Genesis 2:24, where the original divine teaching concerning marriage is found. So if Jesus quotes the Scriptures in order to correct a faulty, permissive divorce practice, then is He a fundamentalist? Is Jesus rigid?"

"How seriously do we take the Gospels? What is left of the Gospel when we start striking out things that Jesus said because we do not want to give them a 'fundamentalist' interpretation, we do not want to be rigid?"

Mercy is another key word in the debate. Fr. Dodaro cautioned that "we have to be careful not to confuse mercy with sentimentalism or romanticism. Love is tough love sometimes."

"So we find mercy by submitting ourselves to the will of Christ, each one of us starting with himself as a sinner, each one of us is called to conversion, each one of us has stuff to figure out in his life."

Commenting on the book that is being released to explain and defend Church teaching on marriage, Fr. Dodaro rejected claims that it was intended as a personal attack.

"I am a university professor, I write articles, I publish books and sometimes other people write articles and books saying: Dodaro is wrong about something. This is a normal part of academic life," he said.

"I do not see the book as polemical in the sense of being angry or of trying to 'gang up' on the Cardinal, as some journalists have suggested."

Rather, he said, the book tries to argue objectively and with well-founded arguments, and the dialogue that has arisen is fruitful.

"As a famous university professor, Cardinal Kasper should be used to an academic debate: does his solution fit in terms of the Catholic Tradition and teaching? Is it doctrinally acceptable? Or would it imply a radical change in teaching? That is the nature of the debate."

Fr. Dodaro holds out hope for the upcoming gathering of bishops in Rome: "The themes of marriage and family concern all Catholics, and I think part of what Pope Francis wants to do is to emphasize the positive role of joy in Christian life."