"I am extremely concerned for you that those around you have led you to believe, or encouraged you in your own belief, that it is in any way 'cool' to be naked and licking sledgehammers in your videos," O'Connor's letter said. "It is in fact the case that you will obscure your talent by allowing yourself to be pimped, whether its the music business or yourself doing the pimping."
UPDATE: Miley Cyrus has since posted a tweet comparing Sinead O'Connor to Amanda Bynes, and not in a good way. The "Wrecking Ball" singer posted a screenshot of several crazy, ranting tweets allegedly from O'Connor. In one, the legend asks for a good therapist, and in another she says she must get back on her mediciation.
Miley Cyrus has made headlines recently for her raunchy performance at the MTV Video Music Awards. The singer wore a nude plastic bikini and twerked against Robin Thicke while making suggestive poses with a foam finger. But Sinead O'Connor warned Cyrus not to focus solely on her sex appeal.
Check out video of Miley Cyrus at the Video Music Awards below.
"The music business doesn't give a sh*t about you, or any of us," O'Connor continued. "They will prostitute you for all you are worth, and cleverly make you think its what YOU wanted... and when you end up in rehab as a result of being prostituted, 'they' will be sunning themselves on their yachts in Antigua, which they bought by selling your body and you will find yourself very alone."
Sinead O'Connor also thinks Miley Cyrus is harming more than just herself. The legendary singer warned that the former Disney channel star is setting a bad example for young women.
"Whether we like it or not, us females in the industry are role models and as such we have to be extremely careful what messages we send to other women," O'Connor wrote. "The message you keep sending is that it's somehow cool to be prostituted... it's so not cool Miley... it's dangerous."
Last month, Miley Cyrus told Rolling Stone that she specifically channeled O'Connor in the video for "Wrecking Ball." Indeed, both "Wrecking Ball" and O'Connor's "Nothing Compares 2 U" feature close-ups of the singers with short haircuts. But O'Connor wrote that Cyrus missed the point of the classic video.
"The look I chose, I chose on purpose at a time when my record company were encouraging me to do what you have done," O'Connor continued. "I felt I would rather be judged on my talent and not my looks. I am happy that I made that choice, not least because I do not find myself on the proverbial rag heap now that I am almost 47 yrs of age, which unfortunately many female artists who have based their image around their sexuality, end up on when they reach middle age."
Watch Sinead O'Connor's famous video below.
But Sinead O'Connor is not being so harsh on Miley Cyrus because she does not respect the young star's talent. Rather, O'Connor feels Miley Cyrus can make great music without showing off her sexual side.
"As for the shedding of the Hannah Montana image... whoever is telling you getting naked is the way to do that does absolutely NOT respect your talent, or you as a young lady," she concluded. "Your records are good enough for you not to need any shedding of Hannah Montana. She's waaaaaaay gone by now... Not because you got naked but because you make great records."