The unbelieving Jews were plagued by the effect of their unbelief. They could not accept a simple statement of truth. The one who received his sight could not even convince the Jews in their awful state of unbelief. After questioning the son who had received his sight they turned to the parents and began asking them questions. Instead of believing and accepting the son which was the most reliable source for truth, they took a step a way from truth and went to the parents and thus were incapable of getting the whole truth.
Every religious organization has some degree of truth mixed with error.
For example, much of what is practiced religiously, by the Masonic lodge is truth mixed with error. Even the cult groups such as the Mormons and Jehovah s Witnesses have some truth. The Roman Catholic church is another example. In the case of the Catholic church, they allow their authority to be more than the Scriptures alone, accepting what is known as Papal Authority. Under the authority of the Pope, they can add to the body of truth their own dogma and beliefs.