Concise Bible Dictionary:
A word often used in the Old Testament in opposition to those manifesting wickedness. It occurs only twice in the New Testament: as uttered by Judas in reference to the Lord, to whom it could be truthfully applied as “guiltless”; and by Pilate in reference to himself (Matt. 27:4,24). It was the true state of Adam and Eve before they fell. See HOLINESS.
Strong’s Dictionary of Greek Words:
Meaning:
from 1 (as a negative particle) and probably a derivative of 5087 (meaning a penalty); not guilty