Was the word "SATAN" flashed during the 2021 Super Bowl? No, that's not true. A screengrab showing the word on an on-stage video screen is from a 2017 concert in Denmark, not the February 7, 2021 halftime show at the Super Bowl game in Tampa, Florida.
The claim appeared as a post (archived here) where it was published on Facebook on February 7, 2021 under the title "Called It." It opened:
Satan flashed in the halftime Super Bowl satanic ritual.
This is what the post looked like on Facebook at the time of writing:
(Source: Facebook screenshot taken on Mon Feb 8 19:01:26 2021 UTC)
The screen grab is not video of The Weeknd's (real name Abel Makkonen Tesfaye) live performance at the Super Bowl halftime show at Raymond James Stadium in Tampa, Florida on February 7, 2021.
It is a screen grab from an old video that has been available on YouTube since 2017.
The footage is from The Weeknd's live performance at the Royal Arena in Copenhagen, Denmark on February 21, 2071. It's not clear whether the artist is praising satan, projecting the word for shock value or to emphasize the point of the song.
Here is a short video from the Copenhagen concert on YouTube, with titling in the beginning of the video that reads, "Musical artist The Weeknd performs on stage whilst giving praise to Satan."
At 23 seconds in the video titling reads, "Missed it? Let's have another look in slow motion," and the video slows down so the black letters "SATAN" are seen on the red background screen.
The video notes:
"If you think its not real check the original video at mark 3:00," with a link to the longer version from the concert in 2017 in Copenhagen.