The Greek adjective amemptos (ἄμεμπτος) means blameless, without fault, or irreproachable. Formed from the alpha-privative and memphomai (to blame, find fault), it describes a person or conduct that cannot be legitimately criticized.
Amemptos is used of upright human character and divine expectations. Zechariah and Elizabeth were 'blameless (amemptoi) in observing all the Lord's commands and decrees' (Luke 1:6). Paul writes to the Thessalonians of his hope that they will be 'blameless (amemptous) in holiness' at Christ's return (1 Thessalonians 3:13). Crucially, Philippians 3:6 shows Paul's pre-conversion self-assessment: 'as for legalistic righteousness, blameless (amemptos)' — yet he counted it loss. True blamelessness is not moral achievement but grace-worked conformity to Christ.