(CNN) On Saturday, former White House chief of staff John Kelly told a conservative audience about this piece of advice he gave President Donald Trump before leaving his job:

"I said, whatever you do -- and we were still in the process of trying to find someone to take my place -- I said whatever you do, don't hire a 'yes man,' someone who won't tell you the truth -- don't do that. Because if you do, I believe you will be impeached."

Kelly's comments drew a decent amount of attention right after he made them -- at a conference in Sea Island, Georgia sponsored by the Washington Examiner -- but got lost the second Trump tweeted "something very big has just happened!" just before 9:30 p.m. ET Saturday night. That tweet -- and Trump's subsequent Sunday morning announcement that ISIS leader Abu Bakr al-Baghdadi was dead -- overwhelmed all other news.

But we shouldn't let the constant churn of covering Trump roll right over what Kelly said and why it's both telling and damning about this President. (Worth noting: Trump denied that Kelly had told him any such thing; "If he would have said that I would have thrown him out of the office," Trump said in a statement . "He just wants to come back into the action like everybody else does.")

Consider carefully exactly what Kelly is saying here: If the President of the United States is allowed to do what he wants, he will act in ways that will lead to his impeachment.

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