You are right. There are certain criteria to either accept or to either consider a person as an enlightened person or to be treated as a true teaching, as per vedic texts. Like the terms Savikalpa Samadhi, Nirvikalpa samadhi, Jeevan Mukta, Para mukta etc stages. Of course, we cannot trust blindly every tom, dick andharry, who takes the name of GOD, by mere external senses, but had no real experiences of GOD, or for that matter had not freed self from the clutches of the nature and its bondages.
Please read the book "Autobiography of a Yogi" by Swami Paramahansa Yogananda or his other commentary on Bhagavad Geetha in the book "GOD TALKS WITH ARJUNA".
You will get more details on the experience based spirituality.
Swami Ramakrishna Paramahamsa says that: Knwoledge obtained by way of reading books is GOOD. Knowledge obtained by of a person who had an experience of the things is BETTER. Knowledge obtained by way of self experiences is BEST.
This above was especially true in the path of Spirituality. Holy scrpitures and books can help the people as sign posts, like the way sign posts help while we are on the road journey from a source to destination.
