“Deliberate cruelty is not forgivable! It is the one unforgivable thing, in my opinion, and the one thing of which I have never, never been guilty.”
Context: Blanche confronts Stanley shortly before he assaults her, defending her own moral code.
Analysis
The emphatic repetition "never, never" and the absolute "unforgivable" set Blanche's gentility against Stanley's brutality, defining her values just before he violates them. The dramatic irony is brutal: this moral line is spoken moments before Stanley commits the most "deliberate cruelty" in the play. Williams uses it to indict Stanley and to elevate the defenceless Blanche.
Language Techniques:
Exam Tip
Use for the theme of cruelty and violence. The placement directly before the rape makes the irony devastating — quote it against Stanley's actions.