From Vatican News: 

After a meeting in the Apostolic Palace earlier in the morning, Pope Leo XIV, King Charles III and Queen Camilla of Great Britain gathered together for an ecumenical prayer service in the Sistine Chapel. They were joined by the Most Reverend Stephen Cottrell, the 98th Archbishop of York and the Primate of England – the second-most senior bishop in the Church of England.

The Pope and Archbishop led a midday prayer comprising psalms and a Gospel reading. Michaelangelo’s frescoed chapel was filled with a number of ecumenical guests, including the Archbishop of Westminster and President of the Catholic Bishops’ Conference of England and Wales, Cardinal Vincent Nichols, and the Archbishop of St Andrews and Edinburgh, Leo Cushley, representing the Scottish episcopate.

This visit marked a historic moment in Anglican-Catholic relations—one that has not occurred in 500 years. Two themes marked the journey: Christian unity and care for the environment.

Originally scheduled for April, the visit was cancelled due to Pope Francis’ ill health. One of its goals was to highlight the shared commitment of King Charles and the Argentine Pope to the care of Creation — ten years after the publication of the encyclical Laudato si’.

Moreover, the ecumenical prayer service, held in Latin and English, built upon the good relations between the Vatican and the United Kingdom. It also fulfilled a wish of King Charles, who, as Supreme Governor of the Church of England, has long been committed to interfaith engagement.

From the opening hymn of the prayer service, the theme of Christian unity and ecumenism was evident. The original text was written by St. Ambrose of Milan, Doctor of the Church. It was translated by St. John Henry Newman, who was an Anglican for half of his life before converting to Catholicism.

King Charles had attended the canonization ceremony of the English theologian in 2019. St. John Henry Newman is set to be declared a Doctor of the Church on 1 November by Pope Leo.

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The New York Times, noting that the new Archbishop of Canterbury is, for the first time, a woman adds:

In theory, there is no reason the pope cannot conduct future prayer services with a female archbishop of Canterbury, said Anna Rowlands, a political theologian at Durham University in England. “She will be, once installed, the head of a fellow Christian ecclesial community” that the Catholic Church has a relationship with, Professor Rowlands said.

Leo’s praying with King Charles does not represent a meeting of the minds on other issues that may divide the churches, theological experts said.

Anglican priests can be married and some Anglican churches allow openly gay priests, while the Catholic church demands that clerics remain celibate and prohibits openly gay clergy. Divorced Catholics who have not had their marriages annulled may not remarry in a church service, while divorced Anglicans can.

“We don’t have to change each other,” said the Very Rev. Andrew McGowan, a professor of Anglican studies at the Yale Divinity School.

Experts said it was unlikely that the pope or the king would bring up divisive issues. “There’s certain topics you don’t bring up at Thanksgiving dinner,” said Rev. Thomas J. Reese, a senior analyst at Religion News Service and a longtime Vatican analyst. “You know where everybody stands, and so the effort is to see where we can work together.”

Below is full video of the service. The King and Queen enter at the 19 minute mark.