If one wishes to make a journey, the first thing one must know is the destination. Where are you trying to go? The second thing one must know is how to get there, which can only be learned from someone who has already been.
If this is common sense in life, why is it that when people undertake a spiritual journey, they often imagine that they will reach their destination without any clear sense of where they intend to go or any effort to seek a competent guide? It is almost as though people bounce from one teaching to another, hoping they will be lucky enough to encounter an authentic way.
To complicate matters, the world is filled with many spiritual teachers who claim to have been to the "destination" even though they have not and likely never will.
How is a sincere seeker to know the difference? Let us return to our analogy of a journey. For example, let us say that the year is 1000 AD, and you wish to travel to India, but there are no maps. You must seek a guide - but which to choose? How would you go about it? Furthermore, let us say that you encounter many people who tell you they can show you how, but you have doubts. How would you be confident, or at least reasonably sure, that they are telling the truth?
After some research, you discover a particular thing that can only be found in India (such as a snow leopard, for instance). Now, many of your would-be travel guides may be able to tell you about snow leopards, some quite convincingly so, but you have no way of knowing if they've actually been there or if they're simply repeating stories they heard from someone else. Aside from their stories, there's no sure way to know if they've been there.
Now, suppose you encounter a travel guide who has a snow leopard! You could be quite sure that they have either been there or are very close to someone who has. This is positive proof.
This is the situation that genuine seekers find themselves in when contemplating a spiritual journey. You may have heard stories of extraordinary knowledge or abilities that can only be acquired by undergoing a genuine development journey. Many in the world today can describe these abilities quite convincingly. But who among them can do more than describe them? Who among them can demonstrate advanced esoteric knowledge and abilities? Logic dictates that this should be the sole criterion for following the advice of a spiritual guide. A student should be able to say "prove it" to any assertion their teacher proposes. The teacher should be able to prove it without excuses, hesitation, or exception. A teacher who cannot or will not do so is to be avoided. In the beginning, faith should never have to enter into the equation. Later, perhaps, but never in the beginning.
And so, to begin this journey on sound and reasonable footing, you must become accustomed to questioning everything you learn. Ask for proof. Better yet, try to disprove the assertions of this teaching - and if you do, let us know.