Broadcaster Adrian Chiles aims to do something unfashionable in his new series on religion: focus on ordinary people rather than fanatics.

A practising Roman Catholic, Chiles took a tour of Mediterranean for the two-part My Mediterranean series, which starts on Sunday.

His personal odyssey begins in Croatia, which is his mother's homeland. On his travels he meets Christians, Muslims and Jews, and is convinced that most quiet people of faith – of whichever religion – are a force for good but just don't get enough coverage.

"Jesus said the meek shall inherit the Earth; well they might, but they're not getting much media attention along the way," he says.

On the island where his mother now spends much of her time, he recalls going to church as a little boy with his grandmother, and being gently mocked by his atheist parents for praying. His mum tells him she was turned off religion when, under pressure from the priest at her first confession, she lied by admitting to a sin she hadn't committed. "How can I have got to 48 and a half," he asks her, "and only now be hearing this for the first time?"

Next, he travels to Istanbul, where a Muslim family invites him to celebrate the festival of Eid, which he enjoys enormously, except for the part where he has to eat a lamb he's just witnessed being sacrificed. He says: "I came here a Catholic; I'm going to go home a vegetarian."

Chiles became a Roman Catholic nine years ago and the series opens with him saying "I believe in God." He continues: "On my journey around the Mediterranean I want to show that religion actually does more good than harm. I won't be seeking out the religious zealots – they get quite enough airtime if you ask me. I just want to find the majority; the nice, normal, gentle people who happen to be religious."

He told the Independent that BBC2 controller Kim Shillinglaw commissioned the programme after he told her how he and a Muslim taxi driver had a late-night discussion, bade each other farewell with a "God bless you", and, he concluded, "there wasn't a piece of paper between us".

Chiles – who attended mass on each of the 46 days of Lent last year – plans a "Lent Live" project this year, visiting various churches and faiths – "Gurdwara, Humanist, Quaker, Druids" – recording the project for radio or print media, as television chiefs "just weren't interested".

My Mediterranean is on BBC 2 on Sunday at 9pm.