To stand upon one's pantables. To stand upon one's dignity. Pantables are slippers, and the idea is se tenir sur le haut bout - i.e. to remit nothing.
“Hee standeth upon his pantables and regardeth greatly his reputation.” —Saker: Narbonus (1590).
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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