Oh. In context it's saying people are dependent on their traditions and scriptures as if they were the "key" to eternal life. The key to eternal life is in the physical person christ and the laws he spoke of are oral and "presented" in his passion as so said. So, people are more focus on the physical when the bible puts more emphasis on the spirit-ual and abstract.
The physical scriptures don't give eternal life. WHO the scriptures speak of does. That's what that means.
John 5:39 You pore over the Scriptures because you presume that by them you possess eternal life. These are the very words that testify about Me,
38nor does His word abide in you, because you do not believe the One He sent. 39You pore over the Scriptures because you presume that by them you possess eternal life. These are the very words that testify about Me, 40yet you refuse to come to Me to have life.… (With cross references)
If christians look to christ as the foundation of scriptures rather than scriptures than a foundation of christ, they wouldn't need scripture to have a relationship with christ. Scripture says the relationship was based on faith not on sight. So, if christ came in person here, many christians would search their bible for confirmation rather than listen to the person with whom the scriptures speak of.