Sinead O'Connor has announced she has converted to Islam and changed her name to Shuhada' Davitt.
The controversial Irish singer, best known for her song Nothing Compares 2U, revealed the news on Twitter.
The 51-year-old said: "This is to announce that I am proud to have become a Muslim.
"This is the natural conclusion of any intelligent theologian's journey.
"All scripture study leads to Islam. Which makes all other scriptures redundant. I will be given (another) new name. It will be Shuhada'."
The tweet, posted on 19 October, was followed by messages apparently from the Koran as well as selfies of her wearing a hijab.
Davitt has also changed her Twitter name to her new title.
Her profile picture shows the Nike tick accompanied with an adaption of the brand's famous slogan, which reads: "Wear a hijab, just do it."
The singer also shared a picture of herself standing in front of a board with a message reading: "You have taken my body, you have taken my mind, you have taken my children but you will never take my voice."
She also posted a video where she sings the Azan, or call to prayer, and acknowledges she makes some pronunciation mistakes.
Davitt said the "emotions took me from my page... but they'll be hundreds of others onstage to come".
She wrote on Thursday: "Thank you so much to all my Muslim brothers and sisters who have been so kind as to welcome me to Ummah today on this page.
"You can't begin to imagine how much your tenderness means to me."
Davitt was ordained as a priest in 1999 by a Catholic group not connected to the Roman Catholic Church, of which she has been a vocal critic.
She ripped up a picture of the late Pope John Paul II during a Saturday Night Live appearance in 1992.
The singer has a history of mental health issues.
In June 2016 she dismissed reports she was missing and had threatened to jump off a bridge, calling the report "false and malicious gossip".
She wrote on Facebook in December 2015 that she had been detained in hospital for a mental health evaluation.
A month earlier she wrote another Facebook post claiming she had overdosed on pills in a hotel room in Ireland.
She was later found safe and taken to hospital.