John 1:39 (NIV)
and you will see.
The Pharisees claimed to see but were blind. When we're filled with our own legalistic righteousness, we fail to understand what the gospel is about, that it is about walking in love and not about not trying to sin. As much as we are commanded to keep ourselves free from sin, we are commanded even more to love. When we are obsessed with our own personal holiness, we try to cleanse ourselves when in reality only the love of Christ can purify us. The Pharisees could clean themselves on the outside but were rotting on the inside. To see and understand as the Lord would have us, we have to walk in love and not the law.