Context be damned, Batman V Superman: Dawn of Justice director, Zack Snyder, posted an image of Superman aka Henry Cavill in a robe over his costume posing as a Jedi with a lightsaber. The internet was not designed to handle this level of geektastic imagery.
Seldom does Snyder tweet and this could just be a clever photoshopped image he wanted to share with this followers (most likely). Or it could be a preview of the Star Wars solo film he was picked to direct (probably not). Or as Batman-News surmised it could just be a shopped image from the set where the actors are said to be wearing robes between takes to hide from any onlookers with cameras (probable). Sure would be nice if Snyder would expand on this. Oh well.