In a string of Instagram Story posts Thursday, Bieber shared lyrics to Tool's "The Pot" and said he was curious to know if many of his fans were familiar with the song. He then let the song play for over minute in a handful of ensuing videos.
When the news reached Keenan, he replied bluntly via Twitter to Consequence of Sound with "#bummer."
On August 30, Tool is expected to release its new album, the band's first since 2006's 10,000 Days. Tool has yet to announce a tour in support of the record.
Bieber has expressed his appreciation of other rock artists before.
There's video of him singing the guitar lead to Metallica's "Fade to Black" in a dressing room from a couple years ago and he famously dressed as Ozzy Osbourne to perform "Crazy Train" on a 2015 episode of Lip Sync Battle.
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