[PW] "The Dude abides"

[Jeanne Schramm]

Hi All!  This is for me, so -- as we usually say -- there's no rush.
Actually it's for my mother.  She often misses the point in her daily comic
strips, and she calls on me for an explanation. Recently she has been seeing
the expression "The dude abides" in the Mutts strip.  I know it's a quote
from "The Big Lebowski."  I've read several reviews but (since I haven't
seen the movie and don't know the context) I can't come up with anything
that actually makes good sense to my mother'  Can anyone help?   Thanks!
Jeanne Schramm, West Liberty, WV