ROME — At first, Pope Francis did not want to celebrate a Catholic Mass in Sweden in order to preserve Monday’s ecumenical witness at the joint Catholic-Lutheran commemoration of the Reformation in Lund, he revealed in an interview released today.

He later changed his mind after reflecting on his role as pastor of the Catholic community, and in response to a request from the local Church. But he put the Mass on the following day, Tuesday, in order to “avoid confusing” the ecumenical event with the Catholic one.

The pope revealed his decision-making process in an interview with the Swedish Jesuit journal Signum released in English October 28 on the website of Civiltà Cattolica magazine.

In the interview with Father Ulf Jonsson, a fellow Jesuit, the pope also discusses his relationships with Lutherans from his days as a Jesuit and later archbishop in Buenos Aires, and said Catholics could learn from the Lutheran tradition in the areas of church reform and Scripture.

Noting how the words “Catholic” and “sectarian” were in contradiction, he said: “This is why at the beginning I wasn’t planning to celebrate a Mass for the Catholics on this trip. I wanted to insist on an ecumenical witness.”

“Then I reflected well on my role as pastor of a flock of Catholics who will also come from other countries, like Norway and Denmark,” he said. “So, responding to the fervent request of the Catholic community, I decided to celebrate a Mass, lengthening the trip by a day.”

By celebrating the Mass on Tuesday, rather than Monday, “the ecumenical encounter is preserved in its profound significance according to a spirit of unity — that is my desire,” the pope said.

“This has created organizational issues, I know, because I will be in Sweden for All Saints Day, which is important here in Rome. But in order to avoid misunderstanding, I wanted it to be so.”

The future pope first stepped inside a Lutheran church aged 17 in Buenos Aires for the wedding of a Lutheran colleague at the laboratory where he worked part-time. Years later, while teaching as a Jesuit at the Colegio Máximo, he became close to a Lutheran professor of spiritual theology, Anders Ruuth, after he invited him to lecture there.

“That was a truly difficult time for my soul,” he recalled. “But I had a lot of trust in him and opened my heart to him. He helped me a lot in that moment.”

Pope Francis also described attending the so-called Swedish church in Buenos Aires while an auxiliary bishop in the early 1990s, and later — as cardinal-archbishop — having what he describes as a “good relationship” with the pastor of the Danish Lutheran church in Buenos Aires, with whom he had a disagreement over “a law concerning religious issues in Argentina.”

Asked what the Catholic Church could learn from the Lutheran tradition, Pope Francis said Martin Luther “wanted to remedy a complex situation” but his reform ended up splitting the Church because of the confusion of temporal and spiritual.

But he said reform in the Church was “fundamental, because the Church is semper reformanda (always to be reformed),” adding that prior to the 2013 conclave “the request for a reform was alive” in the cardinals’ discussions about the state of the Church.

He said Catholics could also learn from Luther’s emphasis on Scripture.

“Luther took a great step by putting the Word of God into the hands of the people,” he said.