By Samantha Highfill
Updated December 15, 2014 at 03:30 PM EST

Samuel L. Jackson has a message to any and every celebrity who participated in the Ice Bucket Challenge over the summer: There’s a new challenge waiting for you.

Over the weekend, while many people around the nation protested the deaths of Eric Garner and Michael Brown, Jackson posted a video on his Facebook page that asked celebrities to join in by singing the “‘We ain’t gonna stop till people are free’ song.” He then kicked off the challenge himself: