All 3 Uses of

muster
in
The Poisonwood Bible

But she mustered manners enough to make orange juice, of which the chief was fond.†
Chpt 3 *

mustered = gathered

So it was to be just the Price family and whatever help we could muster up.†
Chpt 1

It is hard to muster up the proper respect for a chief who wears glasses with no glass in them (he seems to think they raise his intelligence quotient), and the fur of a small animal clasped around his neck, a fashion trademark he shares with the elderly churchgoing ladies of Georgia, charmed I'm sure.†
Chpt 2

Definitions:

(1) (muster as in: muster strength or the crew)
to gather
The exact meaning of this sense of muster is often subject to its context. For example:
- "mustered her courage/strength/a smile" -- to gather from within
- "muster the soldiers/crew" -- to gather -- typically for inspection
- "muster volunteers/votes" -- to gather enough to do something
(2) (muster as in: didn't pass muster)
inspection -- especially of soldiers or a crew
(3) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

More rarely, muster can refer to a counting or census. Much more rarely, muster can refer to a call to duty such as compulsory military service or jury duty. In that sense, you may see the expression muster in or muster out. Still more rarely, a muster can refer to a group of peacocks.