A.T. Robertson Commentary Matthew 23:27

"Woe unto you, scribes and Pharisees, hypocrites! for ye are like unto whited sepulchres, which outwardly appear beautiful, but inwardly are full of dead men`s bones, and of all uncleanness." — Matthew 23:27 (ASV)

Whited sepulchre (ταφοις κεκονιαμενοις). The perfect passive participle is from κονιαω and that from κονια, dust or lime. Whitened with powdered lime dust, the sepulchres of the poor in the fields or the roadside. Not the rock-hewn tombs of the well-to-do. These were whitewashed a month before the passover that travellers might see them and so avoid being defiled by touching them (Numbers 19:16). In Ac 23:3 Paul called the high priest a whited wall. When Jesus spoke the sepulchres had been freshly whitewashed. We today speak of whitewashing moral evil.