As she takes up her new post as vicar of Belmont and Pittington in County Durham, Dr Threlfall-Holmes has a vision for the church to be vibrant and exciting.
She admits that people are being put off attending church because they find it boring.
Dr Threlfall-Holmes is an academic specialising in church history and comes to the post after being Interim Principal of Durham University's Ustinov College.
She argues that the church has always had to adapt to new situations, and needs to be addressing 21st century issues.
Dr Threlfall-Holmes said: "I think it is important to answer the questions people are asking now and not those they were asking four hundred years ago. There is a danger that we retreat into a historical golden age. We need to acknowledge that society has changed.
"The church needs to be challenging. It needs to be exciting for people. We need to enthuse people about the idea of Jesus so that it's not a case of why don't they believe but rather how can they not?"
Although her new parish is well attended, Dr Threlfall-Holmes says there is still a need to engage more with children and young families.
"There has been an increase in young families as new families move in to the area. There is a huge appetite to engage with them, through schools and celebrations as well as through church activities," she said.
She already has lots of ideas to utilise the church's prominent position in Belmont, such as running an Easter garden with local school children.
"I want to have people talking about what the church does, to have people talking about God, whether or not they come to church services," she said.
"We need to accept that Church has sometimes been boring for some people. So there are two things we have to do. First, we need to make sure everything we do as a church is really high quality, and secondly we mustn't wait for people to come to us, but go out to where people are, whether it be schools, the local play park or the shopping areas."
Dr Threlfall-Holmes is about to launch her new book, the Essential History of Christianity, at Durham Cathedral on 17 October.
The book has been written with the intention of making Christianity accessible to a wide range of readers.