In the new book, 'Why a Saint?' by Monsignor Slawomir Oder, the Vatican "postulator" in-charge of the late Pontiff's canonisation process, has claimed the Polish-born Pope whipped himself as an act of penance and self-flagellation as a bishop in Krakow and continued to do so after he became the Pope.
"As members of the Pope's close entourage heard with their own ears, Karol Wojtyla used to flagellate himself. In his wardrobe, among his vestments, there hung on a clothes hanger a special belt for trousers which he used as a whip," the British media quoted Monsignor Oder as saying in the book.
He has also claimed that self-flagellation performed by the Pope, who has been put on the fast track to sainthood by the Vatican, was "an instrument of Christian perfection" emulating the sufferings of Jesus Christ.
The fact that Pope John Paul, who died five years ago, whipped himself in bodily penance was first claimed last year by Sister Tobiana Sobodka, a Polish nun who worked in his Vatican apartment and at the papal summer residence at Castel Gandolfo in the hills south of Rome.
"Several times he would put himself through bodily penance. We're in the next room at Castel Gandolfo. You could hear the sound of the blows when he flagellated himself," the Sister had claimed.
Msgr Oder has also claimed in the book that John Paul, had also decided that in the event of an "incurable sickness" he would voluntarily step down as Pope rather than staying on in office until his death.