Cardinal Brandmüller defended the dubia, saying that many people were concerned by the situation in the Church

Cardinal Walter Brandmüller, one of the two living cardinals to have signed the dubia addressed to Pope Francis, has spoken out against the “heresy” of believing in divorce and remarriage.

In a lengthy interview with Frankfurter Allgemeine, Cardinal Brandmüller, former president of the Pontifical Committee for Historical Sciences, said that the Council of Trent had proclaimed the indissolubility of marriage as a dogma. This means, the cardinal said, that entering a new union after a civil divorce, or continuing a sexual relationship in this new union, is a grave sin.

This has consequences for the Eucharist, the cardinal said: “Whoever is aware of having committed a grave sin can only receive Communion if he has been to Confession, has confessed and has been absolved.”

This teaching has been reaffirmed in recent decades by Pope St John Paul II, Benedict XVI and the Congregation for the Doctrine of the Faith. However, in the aftermath of Pope Francis’s exhortation Amoris Laetitia, some bishops have said that the divorced and civilly remarried can receive Communion, on the basis of the document’s ambiguous footnote 351.

Cardinal Brandmüller said: “I am now being told that the entire moral-theological tradition of the Church can be overruled by a footnote. Here I look to the authority of the Church Fathers.”

To clarify these and other confusions, five dubia – questions – were submitted to the Pope last year by Cardinals Joachim Meisner, Carlo Caffarra (both of whom have since died), and Raymond Burke as well as Cardinal Brandmüller.

In the new interview, the cardinal defended their decision to publish the dubia, after a month in which the Pope neither replied nor acknowledged receipt of their questions. He said they decided to go public because of the concern of many Catholics about the present situation. “We cardinals do not live outside the world,” Cardinal Brandmüller said. “We have many connections. Do you know how many phone calls, letters, questions we get?

“People ask us, among other things: Why aren’t you cardinals doing anything? After all, we have sworn an official oath and are the Pope’s advisers. We asked for an audience and received no answer.”

The cardinal also referred to the 2015 petition in support of the Church’s teaching on marriage and the Eucharist, which received nearly 800,000 signatures. “As it happens, there are still people who can think,” he said. “I am very worried that something will explode. People are not stupid.”

The proposal for Communion for the remarried was originally put forward, at the Pope’s request, by Cardinal Walter Kasper, who claimed that the practice could be found in the early Church – a claim which was heavily criticised by scholars including John Rist.

When the interviewers mentioned Cardinal Kasper’s proposal, Cardinal Brandmüller said it was based on a “single author, whose work was not only slapdash, but also ideological…the whole thing is dishonest history, which is the manipulation of sources. As a historian, I am especially allergic to this. One should never do that.”