What does Luke 11:44 mean?

This is the strongest yet of Jesus' recent condemnations of the Pharisees. It started because Jesus did not rinse His hands before eating according to a man-made tradition of ceremonial cleanness. Scribes developed the Oral Law attempting to keep a fence around the Mosaic law. Their thought was that if Jews followed more legalistic rules, they wouldn't break the Law, and thus would not be in danger of God's judgment.

The regulations themselves were not usually the problem. There may have been thirty-nine different prohibitions developed for the Sabbath, but those restrictions themselves were not necessarily bad. Unfortunately, the Pharisees turned devotion into pride and legalism. Instead of following their own extra-biblical rules in worship to God, they used them to earn praise from other Jews. They enforced burdensome regulations on others (Luke 11:46). In addition, they used their rules to commit injustice, going as far as to steal the homes of widows (Luke 20:47).

On the outside, the religious teachers look holy. In fact, Jesus says, "For I tell you, unless your righteousness exceeds that of the scribes and Pharisees, you will never enter the kingdom of heaven" (Matthew 5:20). But it's all exterior: for show, without substance. On the inside, they are "full of greed and wickedness" (Luke 11:39).

Their evil is hidden. According to the Mosaic law, walking over a grave doesn't make someone unclean. Touching a dead person makes someone unclean for a week (Numbers 19:16). The people don't know that in their hearts, the Pharisees are spiritually dead. Those who follow them are in danger of becoming "twice as much a child of hell" as the Pharisees, themselves (Matthew 23:15).

Later, in Jesus' more detailed diatribe to the disciples, He will compare the Pharisees to whitewashed tombs, "which outwardly appear beautiful, but within are full of dead people's bones and all uncleanness" (Matthew 23:27).