HOW heartening it has been to see the Archbishops of Canterbury and Westminster engaged in so many joint initiatives in recent days - and in practical activities to promote social justice and the common good. The partnership speaks to a constantly deepening friendship between the Church of England and the Roman Catholic Church, the warmth of which was vividly symbolised by the Queen's recent visit to Pope Francis.

The two Archbishops gave a joint interviewon Radio 4's Sunday programme at the weekend. It was "not a stunt", the Archbishop of Canterbury said, but part of an increasing recognition that God has called the two Churches together to co-operate to work for the poor. It was, the Archbishop of Westminster said, a mutual conviction that it is only when faith is put into action on behalf of the poor that it achieves its true "edge of credibility".

The scope for co-operation is significant, the two men said, on everything from foodbanks and night shelters to the huge numbers of children whom the two Churches educate. On the Anglican side is a Parliamentary inquiry into why more people are relying on foodbanks, and the launch of a classroom "War on Wonga" to warn children of the costly trap of payday lending. On the Roman Catholic side, this week an international conference was held in Rome, chaired by Cardinal Nichols, to take forward the interfaith drive to eradicate slavery and human trafficking: it was signed by the Archbishop of Canterbury, the Pope, and the Grand Imam of Al-Azhar University in Cairo.

Again, this was not a pious aspiration, but a combined intent to lobby 50 big multinational businesses to commit themselves to eradicating slavery from their supply chains. The meeting in Rome - of Churches, activists, victims, and police - had clear practical aims: to develop strong cross-border collaboration, to tighten laws across Europe, and to allow victims of trafficking to remain in countries such as the UK longer than the 45 days that they are currently permitted to stay after police have freed them from the thrall of their slavemasters.

The depth of the mutuality between the two largest denominations in Britain goes well beyond the two Archbishops. Churches Together partnerships all across the land testify to that. So did the twinkle between Queen and Pope, which symbolised friendship as well as common purpose. They did not meet at the Apostolic Palace, and so the Queen was able to eschew black. "I wore this because it's Lent," she said to Pope Francis, gesturing to her lilac outfit. "And I wore white to match your gloves," he replied.

The gathering of 16 leading Anglican and Roman Catholic theologians known as the Malines Conversations Group met for five days last week in Canterbury to continue informal dialogue between the two Churches. They were received at Lambeth Palace by Archbishops Welby and Nichols, who said that the group's work on memory, identity, and difference constituted a "laboratory", or effective "pilgrimage", in the improvement of ecu-menical relations.

Perhaps it is significant that CardinalNichols was formed as a priest in Liverpool under the mentorship of Archbishop Derek Worlock, the Roman Catholic episcopal partner to David Sheppard when he was Bishop of Liverpool. Archbishop Welby was Dean of Liverpool before he was consecrated to Durham and translated to Canterbury. The Sheppard-Worlock motto was "Better together". All these decades on, it is still an effective axiom in giving edge to the gospel across not just a city, but an entire nation.

Paul Vallely's biography, Pope Francis: Untying the knots, is published by Bloomsbury.