VATICAN CITY (AP) — Pope Francis and the Orthodox Coptic pope, Tawadros II, delivered a joint blessing Wednesday from St. Peter’s Square in a significant ecumenical gesture to commemorate the 50th anniversary of a historic meeting of their predecessors.

Tawadros, the Orthodox Coptic patriarch of Alexandria, in Egypt, joined Francis on the stage for the entirety of Francis’ weekly general audience. He delivered a lengthy speech at the start in Arabic and then joined Francis in blessing the crowd at the end on a rainy Wednesday morning.

In welcoming Tawadros to the Vatican, Francis recalled that Wednesday marked the 50th anniversary of the meeting of St. Paul VI and Pope Shenouda III, a first between a Catholic and Orthodox Coptic pope. During that May 10, 1973, encounter, the two popes signed a joint statement on their shared faith in Christ and their rejection of proselytism, while also voicing concern for the plight of the Palestinian people and calling for peace in the Middle East.

Since then, relations have only improved, and Francis visited Tawadros in 2017 at the Coptic Orthodox cathedral in Cairo. At the time, Egypt’s Orthodox Christians were reeling from a spate of Islamic militant suicide bombings at churches that killed dozens of people.

Francis has frequently referred to the “ecumenism of blood,” the idea that Catholics and Orthodox — while divided by schism and theological differences — are united in mourning religiously inspired violence against Christians. Francis referred Wednesday in particular to the 2015 beheading of 21 mostly Egyptian Coptic Christian workers in Libya.

“And speaking of martyrs of the Coptic Church, who are ours as well, I want to remember the martyrs on the Libyan beach, who were made martyrs a few years ago," Francis said.

Tawadros’ visit will culminate with another ecumenically important event when he celebrates an Orthodox Coptic liturgy Sunday at Francis' cathedral in Rome, the Basilica of St. John Lateran.