Meaning "an assembly or act of gathering troops" is from c. 1400. Meaning "a register or roll of troops mustered" is from 1560s. To pass muster "undergo review without censure" is by 1620s; in the form pass the musters it is attested from 1570s.

pass muster, to. To meet a required standard. This term originated in the military and once meant to undergo review without censure. George Gascoigne used it figuratively in 1575: “The latter verse is neither true nor pleasant, and the first verse may pass the musters” (The Making of …

Soon enough pass the muster started to drop its the, and pass muster began to be used in general and non-military senses, with the meaning it has today: “to gain approval or acceptance.” This sort of potted history of a word or phrase is very satisfying, since it is not immediately apparent to many people why we use these words together as we do, yet the explanation is …

It's actually Pass Muster and it's origin is in the military. It means to pass inspection. It means to pass inspection. Muster is the Naval equivalent of forming rank and …

"Such excuses will not pass muster with God." Muster Hence: To summon together; to enroll in service; to get together. "Mustering all its force ." "All the gay feathers he could muster ." "One of those who can muster up sufficient sprightliness to engage in a game of forfeits." Muster Something shown for imitation; a pattern.