Well, look at this:
Luke 1:5-6 There was in the days of Herod, the king of Judaea, a certain priest named Zacharias, of the course of Abia: and his wife was of the daughters of Aaron, and her name was Elisabeth. And they were both righteous before God, walking in all the commandments and ordinances of the Lord blameless.
What do you think that means? Remember too the N.T. doctrine of perfection, which so many also deny these days.
I think they were blameless, but not sinless. If they were sinless the greek word "anamartetos", which means "without sin" would have been used. Instead the greek word "amemptos" was used, which indicates that they were something less than sinless... :-)