Pope Francis will attend the Lutheran World Federation meeting, the first time Catholics and Lutherans will celebrate the Reformation together, on Oct. 31, 2016. The date marks 499 years since 1517 when Martin Luther nailed his 95 theses on the door of Castle Church in Wittenberg, Germany, where he lived and preached.

The Lutheran World Federation and the Vatican have jointly organized the Pope's visit around this meeting, hosted by the Swedish Church in Lund. It is there that the LWF was founded in 1947. Pope Francis' decision to come to the LWF meeting shows his strong commitment to ecumenism and a dialogue between the Catholic and Protestant churches. It is otherwise unusual for a pope to visit a protestant country. John Paul II came to Sweden in 1989, but mainly to meet today's Swedish Catholics, who number about 100,000.

Last summer, the Archbishop of Sweden Antje Jackelén visited the Pope at the Vatican with Queen Silvia and Princess Madeleine and her family. They spoke about refugees and ecumenism, of efforts to protect children from violence and abuse — issues that are close to his heart and for which he has thanked Sweden on several occasions. He appreciates Sweden's long tradition of receiving refugees and the Nordic country's efforts to protect the environment.

It was just a few weeks ago that the Vatican announced Sweden would canonize a new saint, probably in 2016; Elizabeth Hesselblad founded the modern Birgittine order, which now operates in some 50 countries with its mother house located in Rome.

The Pope and the leaders of the Lutheran World Federation will celebrate a joint worship in Lund Cathedral. The service will be open to the public.