A 14th-century manuscript, The Red Book of Ossory, has been returned to St Canice's Cathedral in Co Kilkenny, where it was written 700 years ago.
The manuscript, which was written by Bishop Ledrede, will go on public display for the first time in history from 29 July.
The 79-page vellum artefact is currently in the custody of the Representative Church Body (RCB) Library of the Church of Ireland and was escorted to St Canice's by Chief Librarian and Archivist Susan Hood.
The Red Book is the centrepiece of a new year-long exhibition which will explore life in Ireland in the 14th century.
The book offers offers a glimpse into the life of ordinary citizens through the lens of Bishop Ledrede, who held the See of Ossory from 1317 to 1360.
Speaking on RTÉ’s Morning Ireland, Sally Leadbetter described Bishop Ledrede as "the most extraordinary Bishop to ever hold the See of Ossory".
She said the bishop reserved the Red Book for only "the very essential things for society at the time".
One of these things, she said, was a recipe for 'aqua vitae’, today known as whiskey.
The recipe was used for medicinal purposes in the 1300s as the plague swept Europe.
Ms Leadbetter said it is one of the earliest records of distillation in the world.
The Dean of Ossory, Stephen Farrell, said that Bishop Ledrede was "a man of faith and science, trying to look after the people in his care".
He said the pages about aqua vitae "would be like someone having a recipe for the COVID vaccine today".
Bishop Ledrede was also known for having banned clergy from playing football on the cathedral grounds.
Ms Leadbetter said the bishop "knew that Kilkenny would be a hurling county".
The exhibition will involve four page turns of the manuscript.
The RCB Library will visit every 12 weeks to turn the vellum pages, not just to unveil new passages to the public but also to protect the pages and spine of the ancient manuscript.
The first ‘turn’ will be on the recipe for aqua vitae.