The Right Rev Williams, 56, the former parish priest at St Anthony's in Scotland Road and Our Lady Immaculate in St Domingo Road among others, will be assisted by Father Inch and others associated with St Swithin's.
These will include Father Lawrence Mayne, Father Malcolm Prince and Father Brendan O'Sullivan.
Afterwards there will be a procession of the Blessed Sacrament to the convent chapel, which will become the fifth "church".
It will be a poignant occasion but Father Inch says that the local Catholic community is remaining remarkably upbeat about the future where the preservation of the site's importance is far more important than the church as a building in itself.
"There is a great depth of faith among them people around here and a lot of them have been very understanding," says Father Inch, who originally comes from Wavertree. "They seem to feel that the church of St Swithin's is the mother and that Our Lady of Martyrs is the daughter.
A FASCINATING potted history of the parish of St Swithin's entitled An Ancient Lancashire Mission by RJ Broadbent has remained in print thanks to John O'Dowd and his family.
Retained in the original format from its last reprint in1934 it details the earliest history of Christianity in the Merseyside and Lancashire area through the Domesday Book and the Middle Ages and onwards to the end of the 19th century. It also features some of the earliest photographs of the 1958 church's predecessors, opened on July 21, 1824.
John, who is the landlord of the Lion on Tithebarn Street in the city centre, says copies of the book are still available.
These can be obtained by contacting him at the pub or by phoning 0151 236 1734.