Daryl comes across a subway mural that’s inspired by two different pieces of art: Pieter Bruegel’s The Triumph of Death and Hieronymus Bosch’s The Garden of Earthly Delights.
The Triumph of Death showcases a skeleton army destroying everything in their path. (You can view it here.)
Bosch’s The Garden of Earthly Delights is a triptych (view it here). The image on Sunday’s “TWD” most likely references the right most panel of the oil painting, which depicts Hell through a series of illustrations depicting sin, temptation, and greed all leading to the destruction of man by his own devices.
The mural which Daryl sees seems to be a combination of themes from both.
Man is at war with himself instead of his true enemy, the undead. The petty war between humans ultimately leads to their destruction by the vast horde of walkers who they should be rallying together against.
On a special featurette after the episode on AMC+, showrunner Angela Kang the mural told the story of what happened in the subway tunnels.
“The backstory of it is that there was this massive class struggle that happened. Poeple wound up murdered and stuffed in bags,” Kang said.
“Talking Dead” points out that “people are fighting each other and not the walkers surrounding them” in every section of the mural. It’s also likely the mural symbolizes the conflict playing out between Negan and Maggie’s group in the subway car as the dead similarly surround them.
The mural Daryl sees may foreshadow an impending conflict between Alexandria and the Commonwealth, one which ultimately may be unnecessary if it meant they were stronger as one. Kang hinted that it speaks to a class struggle that we’ll see on the show.