Charles visited the Holy Trinity Brompton church in South Kensington where he was greeted on arrival by Lord Lieutenant of Greater London Sir Ken Olisa, who introduced him to the vicar, Reverend Nicky Gumbel, and faith minister Kemi Badenoch.
He also met representatives from the charitable groups and programmes Aid to the Church in Need, Open Doors, Love Your Neighbour and Love Christmas, Church Planting Group, Refugee Response and St Mellitus College & Peter Stream.
Charles watched a short service, which included hearing testimonies from persecuted Christians who previously lived in Iran, and he donated several “bags of kindness” towards the church’s Love Christmas programme, which supports disadvantaged people.
The Highgrove-branded material bags contain Waitrose Duchy-branded food such as chocolate, crackers, biscuits, mince pies and cupboard staples including lentils and beans.
They are being sent to Afghan refugees, people who lived in Grenfell Tower, prisoners and people who live in deprived areas of London.
Prayers were led during the Advent service by the Bishop of London Dame Sarah Mullally, the Archbishop Angaelos of the Coptic Orthodox Church, Father Julian Large of the Brompton Oratory, and Pastor Agu Irukwu of Jesus House for All Nations.
Charles was seen speaking to refugees during the event and shared a joke with Jose Rad, who is originally from Iran and moved to the UK five years ago.
The prince asked him: “What do you do?” and Mr Rad responded: “I’m a barber, I can cut your hair if you like,” to which Charles then laughed and touched the back of his neck.
Mr Rad, 36, also handed over a bunch of flowers to Charles, to which the prince responded: “Oh I should have brought something for you.”
Speaking to the PA news agency afterwards, Mr Rad said: “I told him about my work, where I’ve been cutting the hair of homeless people and Afghan refugees in my spare time.
“It was lovely (meeting Charles), I loved it. It’s a once in a lifetime opportunity. I’m so happy.”
Later, Charles spoke to people who were packing up the bags of kindness and joked: “I hope I’m not getting in the way.”
He then asked where the parcels are being sent and who else had made donations.
He added: “I’m sure these are greatly appreciated by everyone, merry Christmas to you all.”
Charles also signed the guestbook at the church before departing just over an hour later.
After the prince left, Sir Ken told PA he felt the event went “very well”.
“The high point for me today was seeing the organisers here packing tens of thousands of bags to present to lonely people over Christmas, which is the spirit of what we all stand for,” he said.
“Prince Charles was very pleased to be here. He’s not been here for 10 years, so it was important for him to come back.
“He’s done quite a lot focusing attention on the persecution of Christians, and other faiths, and so he was grateful for what was laid on today.”