There are Theists who support that God's existence and Atheists who do not. But all Theists and Atheists are believers. Because "Do not believe" is again a kind of belief.
For example: You can believe in the God or You can believe in the concept of "No God".
So all Theists and Atheists are believers in some or other way.
It is very easy to believe something, as it creates a sort of comfort.
Because, there is no need to do anything to believe in something. Only the information according to our mindset is needed. So, belief is a play performed by the an Intelligence, which is formed by the Intellect (One of the functions of the mind).
Hence beliefs are like clothes or decoration, but not the core substance.
"Beliefs always change with time, as it is an illusion. Truth never change with time, as it is beyond the time".
What is the way to realize the Truth or the God without BELIEFS?
Therefore with Yoga, we realize the Ultimate Laws of the Being: Law of Transformation, Law of Death and Law of Rebirth, Law of Creation.
It is a pure Science just like Maths, Physics and Chemistry. It is a mathematics of the inner being.
So we have to be changed totally, as our views, way of life, mind shatters completely and something new gets created. And with that new creation within ourselves, we will come in contact with the Truth. Hence Yoga is not a point of changing the beliefs. It is a death and a new birth. Unless you are ready to kill your belief systems, you cannot be reborn to touch the Truth.
So Experience is an inner Experiment.
Yoga is exactly such thing, where it is an existential experiment, with no faith and belief. Only will and courage is needed to experience it.
When we dissect all our illusions and beliefs, a pure substance remains. That is the "Self" or "Soul" or "Atman".
Yoga helps us to do so. It is an Inner Engineering to discover our true Self.
With that thinking, we can create rational or irrational logics, but cannot change the pattern of our Mind to realize the Truth.
We can experience the Truth with a crystal clear clarity by making the mind as a tool.
Yoga is something that we have to be with it to experience. Hence, a Yogi or Yogini is the one who neither believes in everything nor believes in nothing. They just always stay in touch with the Truth.
How such great treasure YOGA came into light in a compiled version ?
He had brought the religion, which is based on the beliefs to the state of science, where no belief is needed.
“ Truth is the always the same. Whoever ponders it will get the same answer.
Buddha, Jesus and Mohammed got the same answer, but the method of working it out may vary this way or that ”
- The Yoga Sutras
He deduced the absolute laws and the structure of the human being's mind. The path shown by him or his principles are as exact as any Mathematical formulae.
By simply doing what he said, the result will happen as it is, just like 2 + 2 = 4.
Hence it is something to be done and known without belief.
But even in that ecstatic stage, Patanjali resisted himself, which is quiet difficult and expressed everything in terms of science.
Reference: The Alpha and the Omega