What does Luke 11:36 mean?
Jesus finishes this section on a hopeful note. Lawyers from Jerusalem and local Pharisees work hard to convince themselves that Jesus does not fit the Old Testament description of the Messiah. Their "seeing" is muddied because their hearts are filled with "greed and wickedness" (Luke 11:39). They follow the leaders in Israel's past who killed God's prophets because they didn't like their messages (Luke 11:47–52).But, if they would reject their sinful attitudes, their thinking would clear and they would rightly perceive that Jesus is the Messiah. Light in their hearts would illuminate the truth. Accepting that truth in their hearts would cause them to emit the light of God's truth to the world.
The religious leaders don't quite get it. While Jesus is teaching, a Pharisee invites Him to dinner (Luke 11:37). The Pharisee sees that Jesus does not follow the extra-biblical regulations the lawyers imposed on the Mosaic law. In this case, that He does not ceremonially wash His hands before He eats (Luke 11:38). Jesus has just made the point that if you have light inside, you shine on the outside. The Pharisees think that if they shine light on their righteous acts, they must be righteous. But their "righteous" acts are nothing but attempts to look good and earn public approval (Matthew 6:5). Inside, they are filled with filth, like unmarked graves (Luke 11:39–44).