Tom Brady posted a cryptic message on Tuesday about "a lying cheating heart" on his Instagram Stories more than a year after he and Gisele Bündchen filed for divorce.

The quote was attributed to the late boxing legend Muhammad Ali. The words came from a speech Ali made at the United Nations in April 1978 about South Africa and the right against apartheid.

Brady captioned the Instagram Stories post, "be proud of the man in the glass."

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"The personality of a person. The ways of a person. His thoughts. His deeds. His actions. Are all based around his heart. For what is a man? A man is his heart," the post read. 

"A lying cheating heart means a lying cheating man. A loving merciful heart means a loving merciful man. A living heart means living man. A dead heart means a dead man. Regardless to a man’s title. Regardless to a man’s rank, wealth or position, if the heart is not great then he cannot be great. But if the heart is great that man remains great under all circumstances, rich or poor, large or small, for it is the heart that makes one large or small."

It is unclear what the message, which was posted days before Christmas, was exactly about. Brady and his model ex-wife filed for divorce in October 2022.

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This past June, he spoke about some of the struggles he has had co-parenting with Bündchen and the need to give his kids a "real solid base and foundation."

"And I think myself and their mom have done an amazing job of providing that, and I think that we're just gonna keep doing it," he told Entertainment Tonight.

"We're never a finished product. The kids aren't finished products," Brady added. "At the end of the day, we're learning along with them. And all you can do is the best you can do with the opportunities that you have, and the challenges you have, and we all have unique challenges to our life that we deal with."

The former Tampa Bay Buccaneers and New England Patriots quarterback noted that failure and "adversities" are what we are defined by.

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"We're all gonna fail. We're all gonna have adversities in life, and I think you're defined a lot by your adversities because those are the things in the end that challenge you to grow the most," Brady noted when asked what advice he would give his children. 

"I mean, life has its ups and downs, professionally, and there's different things that happen in your life personally, and you just gotta continue to understand them emotionally, intellectually, and then as you move forward, try not to make the same mistakes. And just try to keep growing and become a better person by all your different actions."

Brady routinely posts pictures of his children, including the two he shares with Bündchen.

Fox News’ Lauryn Overhultz contributed to this report.

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