The church was consecrated on September 2, 1909, and officially opened for worship the following March.

One of Cessnock's oldest buildings, it has been an integral part of the city's history and spiritual life, hosting thousands of baptisms, confirmations, weddings and funerals.

"St John's is not just a church building, it is a place that symbolises the journey of life," parish priest, the Rev Canon Michelle Hazel-Jawhary, said.

"It's a place where heaven meets Earth; a church that offers God's love, acceptance, forgiveness, mercy and grace to people from all facets of life."

Rev Canon Hazel-Jawhary said this week's celebrations will provide a "trip down memory lane" for people who have been involved in the church's activities over the years.

On Friday night there will be a "Songs of Praise" evening at 6.30pm, followed by a light supper.

A display of gowns from weddings held at the church will be held over the weekend, and a booklet detailing the history of the church's beautiful stained-glass windows will be produced for the celebrations.

Sunday's 9am service will be "Back to Church Sunday", with one service in the parish to celebrate together, with former Cessnock parish priest, now Bishop of Newcastle, Sonia Roulston to be a special guest.

Rev Canon Hazel-Jawhary said it is important to acknowledge the findings of the recent Royal Commission into child abuse in the church, and that the church is doing its best to restore the community's faith.

"As the Anglican church, we are working hard to be a safe church and rebuild trust so that the church is known for helping people seeking to deepen their faith, and find blessings in their lives," she said.