Forget the political appointments of Donald Trump and the scandals in the Church of England. To me the most remarkable event of the week -- the most consequential, as people now like to say -- was the addition of St Isaac of Nineveh to the Roman Martyrology.

This is to do with life and death, belief and salvation. Of course, St Isaac is obscure to us. He lived in the seventh century, overlapping with our St Bede, and wrote in Syriac, a language closely related to that spoken by Jesus Christ. He went off into the desert rather than exercise authority as the Bishop of Nineveh.

Related: Brief History of Assyrians

All Christianity is oriental in origin. St Peter himself spoke Aramaic. Most old churches in the Middle East have been brought close to ruin by wars, and none has suffered more than the Assyrian Church of the East, which claims St Isaac as a great saint.

To make matters worse, the Assyrian Church has been characterised as Nestorian -- guilty of believing false doctrines about the divinity and humanity of Jesus. In an act of friendliness during a visit on November 9 by Mar Awa III, the Catholicos-Patriarch of the Assyrian Church, Pope Francis announced the addition of St Isaac to the Roman Martyrology. The Martyrology lists Catholic saints, not just martyrs.

Related: Timeline of Assyrian History

At their meeting, the Pope emphasised the common faith of the Assyrian Church and the Roman Catholic Church. He was not just improvising. In 1994 a Common Christological Declaration was agreed by the churches. It expresses a thorough faith in Jesus as God and man.

In 2021, the present Pope, already 84 and finding it hard to walk, went to Erbil during a visit to Iraq. The Assyrian Church has its headquarters at Erbil, in the Kurdish region. The Pope said Mass for 10,000 there. "Our martyrs shine together like stars in the same sky," he said then. "From there they call us to walk together, without hesitation, towards the fullness of unity."

Related: The Assyrian Genocide

Pope Francis has often spoken of what he called the ecumenism of martyrdom: "In some countries they kill Christians for wearing a cross or having a Bible; and before they kill them they do not ask them whether they are Anglican, Lutheran, Catholic, or Orthodox."

At the same time, like Mar Awa, he insists on sharing "the same faith, handed down by the Apostles". In practical terms, the Assyrian Church and the Chaldean Catholic Church (which has long formally declared its communion with the Bishop of Rome) have arranged in some circumstances to share the Eucharist, the central act of Christianity, which provides living unity between local churches.

The Assyrians, like the Chaldeans, have an ancient liturgy named after Saints Addai and Mari, followers of St Thomas the Apostle. With its peculiarities it has been fully recognised by Rome.

Mar Awa III, to whom the Pope played host, is from Chicago. The Assyrian church has been so tossed by storms (genocide during the First World War, a massacre in 1933 that sent the Patriarch as a refugee to Cyprus, then America) that it has relied on its diaspora for continuity. Its communities in Syria and Iraq were assailed by war and persecution by Isis. The St Isaac of Nineveh Monastery is now active in Salida, California, 60 miles from San Francisco.

Unity between the Assyrians, Chaldeans and Roman Catholics is no walk in the park. Attempts have succeeded and foundered for the past five centuries. Though the number of Assyrians is fewer than 400,000 now, their culture and practice benefit the universal Church.