The Hebrew word rendered "blameless" (NKJV) or "perfect" (KJV) in Genesis 17:1 means "entire, complete, full, without blemish." The Greek word found in Matthew 5:48 translated "perfect" means "finished, complete, having reached its end," and implies being fully grown or mature. The definition of the English word perfect is "lacking nothing essential to the whole, without defect, complete." All three definitions contain the word "complete."