The shard of glass is a highly intentional narrative tool representing the episode's core theme:

: During his final fistfight with Negan, Rick smashes the glass and uses a sharp shard to slice Negan's throat.

It serves as the visual catalyst that officially ends the brutal "All Out War" story arc between the communities and the Saviors.

: A stained glass window hanging suspended from a tree in the middle of the battlefield.

: Instead of letting Negan bleed out to secure his revenge, Rick immediately orders Siddiq to save Negan's life. 💡 Symbolic Meaning

It delivers physical retribution to Negan for his past atrocities.