What was Jesus talking about when he said to the Pharisees, scribes, and other religious authorities these words about them?

Luke 11:44 (HCSB)
“Woe to you! You are like unmarked graves; the people who walk over them don’t know it.”

Why would it matter if someone walked over an unmarked grave?

These verses from Matthew 23:27-28 (HCSB) give more insight.
27“Woe to you, scribes and Pharisees, hypocrites! You are like whitewashed tombs, which appear beautiful on the outside, but inside are full of dead men’s bones and every impurity. 28 In the same way, on the outside you seem righteous to people, but inside you are full of hypocrisy and lawlessness.

Jesus has already said in several different ways in Matthew 23:1-26 and Luke 11:37-52 that the religious authorities don’t practice what they preach. They tell people to follow the Law of Moses yet they don’t do it themselves. They get in the way of people who are about to enter the kingdom of heaven because they don’t understand the real reason for the rules and they give a bad example in their lives. The “kingdom of heaven” is not about when you die, but a state of awakened consciousness and connection with God here and now. It is about actively participating with God in making the world a better place.

Let us dig deeper on the “unmarked grave” idea. There is a Jewish concept about being defiled by death. Having contact with a dead body will result in you being unable to participate in normal life for seven days. It takes a lot of work to get you ritually pure again. You are essentially a leper – you have to live outside of the camp (or city). You don’t get to live with your family or hang out with your friends.

The rule comes from Numbers 19:11-12 (HCSB) –
11 “The person who touches any human corpse will be unclean for seven days.12 He is to purify himself with the water on the third day and the seventh day; then he will be clean. But if he does not purify himself on the third and seventh days, he will not be clean. 13 Anyone who touches a body of a person who has died, and does not purify himself, defiles the tabernacle of the LORD. That person will be cut off from Israel. He remains unclean because the water for impurity has not been sprinkled on him, and his uncleanness is still on him.

If this wasn’t difficult enough, the cure itself isn’t easy. This isn’t just any water (see verse 12) that is being talked about. The “water for impurity” – rather, the water used to remove impurity – isn’t easy to make. It requires a long and involved process. Here are the instructions for making that.

Numbers 19:1-10 (HCSB)
The LORD spoke to Moses and Aaron, 2 “This is the legal statute that the LORD has commanded: Instruct the Israelites to bring you an unblemished red cow that has no defect and has never been yoked. 3 Give it to Eleazar the priest, and he will have it brought outside the camp and slaughtered in his presence. 4 Eleazar the priest is to take some of its blood with his finger and sprinkle it seven times toward the front of the tent of meeting. 5 The cow must be burned in his sight. Its hide, flesh, and blood, are to be burned along with its dung. 6 The priest is to take cedar wood, hyssop, and crimson yarn, and throw them onto the fire where the cow is burning. 7 Then the priest must wash his clothes and bathe his body in water; after that he may enter the camp, but he will remain ceremonially unclean until evening. 8 The one who burned the cow must also wash his clothes and bathe his body in water, and he will remain unclean until evening. 9 “A man who is clean is to gather up the cow’s ashes and deposit them outside the camp in a ceremonially clean place. The ashes must be kept by the Israelite community for preparing the water to remove impurity; it is a sin offering.10 Then the one who gathers up the cow’s ashes must wash his clothes, and he will remain unclean until evening. This is a permanent statute for the Israelites and for the foreigner who resides among them.

So walking over an unmarked grave and not knowing it would be terrible because you would accidentally become defiled. Whether you know it or not you are still defiled. If the grave is marked you have a chance to avoid it – but if it is unmarked you don’t have a chance. The same is true of the religious authorities that Jesus is talking about. They are defiling people with their examples. So people who look up to them are being dragged down into hell. They don’t realize they are being mislead.

This is why I paraphrased the verse from Luke 11:44 like this in the Condensed Gospel: “Woe to you! You are like unmarked graves. People walk over you not even knowing that they have become defiled.”

While this rendering gives a little more insight into the verse, I felt a further understanding of the Jewish death taboos was helpful, so that is why I have included it here.