An incredulous Don Lemon broke down on Monday why President Donald Trump’s lying about accidentally referring to Apple CEO Tim Cook as “Tim Apple” matters.

“When you lie about anything, you’ll lie about everything,” the host of “CNN Tonight” said. Trump has since offered up two contrastingexplanations for his gaffe at a White House event last week.

But Lemon rolled the tape that undeniably showed Trump making the mistake.

“That was your own ears and your own eyes, OK?” Lemon said. “You heard the man, he said, ‘Tim Apple.’ It’s funny, it’s ridiculous. Right? It is.”

“Why am I talking about this?” Lemon continued. “This is why it matters. Because he’s the president and there’s apparently nothing that is too small, too insignificant for this president to lie about. OK?”

“If you lie about the little things, you’ll lie about the big things,” he added.

Check out the clip here: