Madonna posted a cryptic message on Instagram as her custody battle over her son, Rocco, continues.
On Sunday, The "Living For Love" singer shared a quote from German philosopher Friedrich Nietzsche that read, "One way of measuring the strength of an attacker is by looking at the sort of opponents he needs. You can always tell when something is growing because it will go looking for powerful adversaries or problems."
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Madonna added the caption, "Preach Nietzsche... As we enter the 7 weeks of exile and redemption," along with the hashtag #rebelheart, a nod to her album and current tour.
She also tagged @cityofnopity, an Instagram account that shares black-and-white quotes and pictures of the famous faces who said the inspirational words. Just two days earlier, Madonna also shared one of their posts that featured Marilyn Monroe.
The 57-year-old pop star is in the middle of a custody battle with her ex-husband, Guy Ritchie, over their 15-year-old son, who has since shut down his Instagram account since a hearing was called in December.
A source tells ET that Rocco's lawyers told him to disable his social media account. The teen will return to court soon in order to figure out his current living situation.
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Madonna, meanwhile, has left for Mexico City, where she's set to continue her Rebel Heart Tour on Wednesday after a 10-week hiatus. The tour ends Jan. 28 in Puerto Rico.
Rocco had been on the road with Madonna. He wanted to keep living with his father in London, but last month, a Manhattan Supreme Court judge ruled that he had to return to New York before school started again after the holiday break.
"I'm directing the child to be returned to New York," the New York Daily News quoted Manhattan Supreme Court Justice Deborah Kaplan as saying. "If he wants to stay with his father, he must return to his mother.”
Kaplan also reportedly ordered both Madonna and Ritchie -- who divorced in 2008 after eight years of marriage and also share custody of their adopted son, David Banda -- to not discuss the legal proceedings with their son.
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Madonna is still celebrating her love for Rocco despite the family's difficult time. On Christmas, she shared a sweet throwback of her son captioned, "Merry x-mas to the Sun-shine of my Life!"
Reps for the family have not yet responded to ET's request for comment.