Young people and their families gathered in the Archbishop's Chapel at Lambeth Palace today to celebrate the launch of the community of St Anselm; a monastic-style year-long programme focused on prayer and service to the poor.

It was a relaxed affair; though featuring a number of sombre prayers of commitment and traditional hymns, the service was undoubtedly a celebration - punctuated with worship songs from countries around the world, choral arrangements by the St Martin's Voices were met with bongo drums. The 36 new community members - all aged between 20 and 35 - come from five continents and countries as far flung as Kenya and Australia, and parts of the service were conducted in French, Spanish and Swedish. As Archbishop Justin Welby called each member by name, they stood to acknowledge their new role, declaring "I am here" in their native language; echoing the words of Moses in Exodus 3 which was read at the beginning of the service.

Welby began his sermon with his trademark jovial style. Noting that many bishops have been consecrated in the chapel, he said to appreciative laughter, "this is a place where people have gone from here to suffering, to martyrdom, and here we are today...I'm sorry, that's probably a bad illustration."

He spoke of the importance of grace found in community, adding that St Anselm is not unique or rare, but is rather joining a tradition of religious communities that have existed throughout the centuries. "They are ancient and current reflections of the love of God seen in the Trinity: Father, Son and Holy Spirit, in which people risk everything to emulate that love," he said. "A love that is so great that it overflows infinitely into the world from the Father, in the life, death, resurrection and ascension of Jesus and in the sending of the Holy Spirit. Changed by the love which finds and directs us, changed by that grace, we too are to be sources of love and renewal."

20 of the members will be living in Lambeth Palace as residents, while 16 will continue working and join the community part time. All will follow a 'Rule of Life', drawn from the 6th century monastic group of St Benedict, and will take part in Ignatian prayer, while also following the example of Pope Francis in serving vulnerable people. It's likely to be a far cry from what many are used to; 23-year-old Peter Angelica spoke of coming to London from the US, where he has been working as an analyst in an investment bank. He admitted to having previously had doubts about leaving the noise of New York for monastic living, but said the value of being embedded in a loving community was evident. Another young woman, Frances Germain, has been a doctor working in A&E for the past two years, and will continue to do that alongside her commitments at Lambeth.

The Palace itself has, historically, "been a place of privilege, of power, even oppression in darker times," Welby said, adding - to laughter - that its prison is still usable. But the community will endeavour to embody grace - "the most beautiful word in the language of God".

"In that prison, there was no grace," he said. "In this community, we offer the invitation to grace."

When he became Archbishop, Welby declared that his first priority was for the renewal of prayer and religious life across the Church. Today, he said he hopes the community of St Anselm will be prophetic; challenging both the Church and wider society, and speaking "God's truth to itself and to the world."

"Grace reaches out to those who are going nowhere - to the lost. Even when they think they have everything sorted, or there is no hope," he said, speaking directly to the new members before they took their vows.

"Grace is not hidden only in the holy places, but flaunts itself for us in the open air. In community, you will find grace in the ordinary...the grace of Jesus will find you, and you will discover and be discovered in the most mundane moments. Say yes with great expectation."

The service will be broadcast on BBC Radio 4 this Sunday, 20 September, at 8.10am